X-Git-Url: http://nitlanguage.org

diff --git a/c_src/parser_prod.sep.1.c b/c_src/parser_prod.sep.1.c
index 8ce8ea8..3d2a5f0 100644
--- a/c_src/parser_prod.sep.1.c
+++ b/c_src/parser_prod.sep.1.c
@@ -71,13 +71,15 @@ var5 = 0;
 var5 = var_n->type->type_table[cltype] == idtype;
 }
 if (!var5) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 25);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 25);
+show_backtrace(1);
 }
 var6 = self->attrs[COLOR_parser_nodes__AModule___n_imports].val; /* _n_imports on <self:AModule> */
 if (var6 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_imports", "src/parser/parser_prod.nit", 26);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_imports");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 26);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var6->class->vft[COLOR_abstract_collection__SimpleCollection__add]))(var6, var_n) /* add on <var6:ANodes[AImport]>*/;
 ((void (*)(val*, val*))(var_n->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n, self) /* parent= on <var_n:Object(AImport)>*/;
@@ -100,13 +102,15 @@ var11 = 0;
 var11 = var_n10->type->type_table[cltype12] == idtype13;
 }
 if (!var11) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 30);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 30);
+show_backtrace(1);
 }
 var14 = self->attrs[COLOR_parser_nodes__AModule___n_extern_code_blocks].val; /* _n_extern_code_blocks on <self:AModule> */
 if (var14 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_extern_code_blocks", "src/parser/parser_prod.nit", 31);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_extern_code_blocks");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 31);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var14->class->vft[COLOR_abstract_collection__SimpleCollection__add]))(var14, var_n10) /* add on <var14:ANodes[AExternCodeBlock]>*/;
 ((void (*)(val*, val*))(var_n10->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n10, self) /* parent= on <var_n10:Object(AExternCodeBlock)>*/;
@@ -129,13 +133,15 @@ var20 = 0;
 var20 = var_n19->type->type_table[cltype21] == idtype22;
 }
 if (!var20) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 35);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 35);
+show_backtrace(1);
 }
 var23 = self->attrs[COLOR_parser_nodes__AModule___n_classdefs].val; /* _n_classdefs on <self:AModule> */
 if (var23 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_classdefs", "src/parser/parser_prod.nit", 36);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_classdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 36);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var23->class->vft[COLOR_abstract_collection__SimpleCollection__add]))(var23, var_n19) /* add on <var23:ANodes[AClassdef]>*/;
 ((void (*)(val*, val*))(var_n19->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n19, self) /* parent= on <var_n19:Object(AClassdef)>*/;
@@ -251,8 +257,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 46);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 46);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AModule___n_moduledecl].val = var_new_child; /* _n_moduledecl on <self:AModule> */
 } else {
@@ -266,14 +273,14 @@ var6 = NEW_range__Range(&type_range__Rangekernel__Int);
 var7 = 0;
 var8 = self->attrs[COLOR_parser_nodes__AModule___n_imports].val; /* _n_imports on <self:AModule> */
 if (var8 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_imports", "src/parser/parser_prod.nit", 53);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_imports");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 53);
+show_backtrace(1);
 }
 var9 = ((long (*)(val*))(var8->class->vft[COLOR_abstract_collection__Collection__length]))(var8) /* length on <var8:ANodes[AImport]>*/;
 var10 = BOX_kernel__Int(var7); /* autobox from Int to Discrete */
 var11 = BOX_kernel__Int(var9); /* autobox from Int to Discrete */
 ((void (*)(val*, val*, val*))(var6->class->vft[COLOR_range__Range__without_last]))(var6, var10, var11) /* without_last on <var6:Range[Int]>*/;
-CHECK_NEW_range__Range(var6);
 var12 = ((val* (*)(val*))(var6->class->vft[COLOR_abstract_collection__Collection__iterator]))(var6) /* iterator on <var6:Range[Int]>*/;
 for(;;) {
 var13 = ((short int (*)(val*))(var12->class->vft[COLOR_abstract_collection__Iterator__is_ok]))(var12) /* is_ok on <var12:Iterator[nullable Object]>*/;
@@ -283,8 +290,9 @@ var15 = ((struct instance_kernel__Int*)var14)->value; /* autounbox from nullable
 var_i = var15;
 var16 = self->attrs[COLOR_parser_nodes__AModule___n_imports].val; /* _n_imports on <self:AModule> */
 if (var16 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_imports", "src/parser/parser_prod.nit", 54);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_imports");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 54);
+show_backtrace(1);
 }
 var17 = ((val* (*)(val*, long))(var16->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var16, var_i) /* [] on <var16:ANodes[AImport]>*/;
 var18 = ((short int (*)(val*, val*))(var17->class->vft[COLOR_kernel__Object___61d_61d]))(var17, var_old_child) /* == on <var17:nullable Object(AImport)>*/;
@@ -305,21 +313,24 @@ var21 = 0;
 var21 = var_new_child->type->type_table[cltype22] == idtype23;
 }
 if (!var21) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 56);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 56);
+show_backtrace(1);
 }
 var24 = self->attrs[COLOR_parser_nodes__AModule___n_imports].val; /* _n_imports on <self:AModule> */
 if (var24 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_imports", "src/parser/parser_prod.nit", 57);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_imports");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 57);
+show_backtrace(1);
 }
 ((void (*)(val*, long, val*))(var24->class->vft[COLOR_abstract_collection__Sequence___91d_93d_61d]))(var24, var_i, var_new_child) /* []= on <var24:ANodes[AImport]>*/;
 ((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(AImport)>*/;
 } else {
 var25 = self->attrs[COLOR_parser_nodes__AModule___n_imports].val; /* _n_imports on <self:AModule> */
 if (var25 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_imports", "src/parser/parser_prod.nit", 60);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_imports");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 60);
+show_backtrace(1);
 }
 ((void (*)(val*, long))(var25->class->vft[COLOR_abstract_collection__Sequence__remove_at]))(var25, var_i) /* remove_at on <var25:ANodes[AImport]>*/;
 }
@@ -334,14 +345,14 @@ var26 = NEW_range__Range(&type_range__Rangekernel__Int);
 var27 = 0;
 var28 = self->attrs[COLOR_parser_nodes__AModule___n_extern_code_blocks].val; /* _n_extern_code_blocks on <self:AModule> */
 if (var28 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_extern_code_blocks", "src/parser/parser_prod.nit", 65);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_extern_code_blocks");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 65);
+show_backtrace(1);
 }
 var29 = ((long (*)(val*))(var28->class->vft[COLOR_abstract_collection__Collection__length]))(var28) /* length on <var28:ANodes[AExternCodeBlock]>*/;
 var30 = BOX_kernel__Int(var27); /* autobox from Int to Discrete */
 var31 = BOX_kernel__Int(var29); /* autobox from Int to Discrete */
 ((void (*)(val*, val*, val*))(var26->class->vft[COLOR_range__Range__without_last]))(var26, var30, var31) /* without_last on <var26:Range[Int]>*/;
-CHECK_NEW_range__Range(var26);
 var32 = ((val* (*)(val*))(var26->class->vft[COLOR_abstract_collection__Collection__iterator]))(var26) /* iterator on <var26:Range[Int]>*/;
 for(;;) {
 var33 = ((short int (*)(val*))(var32->class->vft[COLOR_abstract_collection__Iterator__is_ok]))(var32) /* is_ok on <var32:Iterator[nullable Object]>*/;
@@ -351,8 +362,9 @@ var36 = ((struct instance_kernel__Int*)var34)->value; /* autounbox from nullable
 var_i35 = var36;
 var37 = self->attrs[COLOR_parser_nodes__AModule___n_extern_code_blocks].val; /* _n_extern_code_blocks on <self:AModule> */
 if (var37 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_extern_code_blocks", "src/parser/parser_prod.nit", 66);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_extern_code_blocks");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 66);
+show_backtrace(1);
 }
 var38 = ((val* (*)(val*, long))(var37->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var37, var_i35) /* [] on <var37:ANodes[AExternCodeBlock]>*/;
 var39 = ((short int (*)(val*, val*))(var38->class->vft[COLOR_kernel__Object___61d_61d]))(var38, var_old_child) /* == on <var38:nullable Object(AExternCodeBlock)>*/;
@@ -373,21 +385,24 @@ var42 = 0;
 var42 = var_new_child->type->type_table[cltype43] == idtype44;
 }
 if (!var42) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 68);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 68);
+show_backtrace(1);
 }
 var45 = self->attrs[COLOR_parser_nodes__AModule___n_extern_code_blocks].val; /* _n_extern_code_blocks on <self:AModule> */
 if (var45 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_extern_code_blocks", "src/parser/parser_prod.nit", 69);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_extern_code_blocks");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 69);
+show_backtrace(1);
 }
 ((void (*)(val*, long, val*))(var45->class->vft[COLOR_abstract_collection__Sequence___91d_93d_61d]))(var45, var_i35, var_new_child) /* []= on <var45:ANodes[AExternCodeBlock]>*/;
 ((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(AExternCodeBlock)>*/;
 } else {
 var46 = self->attrs[COLOR_parser_nodes__AModule___n_extern_code_blocks].val; /* _n_extern_code_blocks on <self:AModule> */
 if (var46 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_extern_code_blocks", "src/parser/parser_prod.nit", 72);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_extern_code_blocks");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 72);
+show_backtrace(1);
 }
 ((void (*)(val*, long))(var46->class->vft[COLOR_abstract_collection__Sequence__remove_at]))(var46, var_i35) /* remove_at on <var46:ANodes[AExternCodeBlock]>*/;
 }
@@ -402,14 +417,14 @@ var48 = NEW_range__Range(&type_range__Rangekernel__Int);
 var49 = 0;
 var50 = self->attrs[COLOR_parser_nodes__AModule___n_classdefs].val; /* _n_classdefs on <self:AModule> */
 if (var50 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_classdefs", "src/parser/parser_prod.nit", 77);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_classdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 77);
+show_backtrace(1);
 }
 var51 = ((long (*)(val*))(var50->class->vft[COLOR_abstract_collection__Collection__length]))(var50) /* length on <var50:ANodes[AClassdef]>*/;
 var52 = BOX_kernel__Int(var49); /* autobox from Int to Discrete */
 var53 = BOX_kernel__Int(var51); /* autobox from Int to Discrete */
 ((void (*)(val*, val*, val*))(var48->class->vft[COLOR_range__Range__without_last]))(var48, var52, var53) /* without_last on <var48:Range[Int]>*/;
-CHECK_NEW_range__Range(var48);
 var54 = ((val* (*)(val*))(var48->class->vft[COLOR_abstract_collection__Collection__iterator]))(var48) /* iterator on <var48:Range[Int]>*/;
 for(;;) {
 var55 = ((short int (*)(val*))(var54->class->vft[COLOR_abstract_collection__Iterator__is_ok]))(var54) /* is_ok on <var54:Iterator[nullable Object]>*/;
@@ -419,8 +434,9 @@ var58 = ((struct instance_kernel__Int*)var56)->value; /* autounbox from nullable
 var_i57 = var58;
 var59 = self->attrs[COLOR_parser_nodes__AModule___n_classdefs].val; /* _n_classdefs on <self:AModule> */
 if (var59 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_classdefs", "src/parser/parser_prod.nit", 78);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_classdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 78);
+show_backtrace(1);
 }
 var60 = ((val* (*)(val*, long))(var59->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var59, var_i57) /* [] on <var59:ANodes[AClassdef]>*/;
 var61 = ((short int (*)(val*, val*))(var60->class->vft[COLOR_kernel__Object___61d_61d]))(var60, var_old_child) /* == on <var60:nullable Object(AClassdef)>*/;
@@ -441,21 +457,24 @@ var64 = 0;
 var64 = var_new_child->type->type_table[cltype65] == idtype66;
 }
 if (!var64) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 80);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 80);
+show_backtrace(1);
 }
 var67 = self->attrs[COLOR_parser_nodes__AModule___n_classdefs].val; /* _n_classdefs on <self:AModule> */
 if (var67 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_classdefs", "src/parser/parser_prod.nit", 81);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_classdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 81);
+show_backtrace(1);
 }
 ((void (*)(val*, long, val*))(var67->class->vft[COLOR_abstract_collection__Sequence___91d_93d_61d]))(var67, var_i57, var_new_child) /* []= on <var67:ANodes[AClassdef]>*/;
 ((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(AClassdef)>*/;
 } else {
 var68 = self->attrs[COLOR_parser_nodes__AModule___n_classdefs].val; /* _n_classdefs on <self:AModule> */
 if (var68 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_classdefs", "src/parser/parser_prod.nit", 84);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_classdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 84);
+show_backtrace(1);
 }
 ((void (*)(val*, long))(var68->class->vft[COLOR_abstract_collection__Sequence__remove_at]))(var68, var_i57) /* remove_at on <var68:ANodes[AClassdef]>*/;
 }
@@ -530,16 +549,18 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__AModule___n_moduledecl].val; /* _n_moduledecl on <self:AModule> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 103);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 103);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
 }
 var4 = self->attrs[COLOR_parser_nodes__AModule___n_imports].val; /* _n_imports on <self:AModule> */
 if (var4 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_imports", "src/parser/parser_prod.nit", 105);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_imports");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 105);
+show_backtrace(1);
 }
 var5 = ((val* (*)(val*))(var4->class->vft[COLOR_abstract_collection__Collection__iterator]))(var4) /* iterator on <var4:ANodes[AImport]>*/;
 for(;;) {
@@ -554,8 +575,9 @@ CONTINUE_label: (void)0;
 BREAK_label: (void)0;
 var8 = self->attrs[COLOR_parser_nodes__AModule___n_extern_code_blocks].val; /* _n_extern_code_blocks on <self:AModule> */
 if (var8 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_extern_code_blocks", "src/parser/parser_prod.nit", 108);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_extern_code_blocks");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 108);
+show_backtrace(1);
 }
 var9 = ((val* (*)(val*))(var8->class->vft[COLOR_abstract_collection__Collection__iterator]))(var8) /* iterator on <var8:ANodes[AExternCodeBlock]>*/;
 for(;;) {
@@ -570,8 +592,9 @@ CONTINUE_label13: (void)0;
 BREAK_label13: (void)0;
 var14 = self->attrs[COLOR_parser_nodes__AModule___n_classdefs].val; /* _n_classdefs on <self:AModule> */
 if (var14 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_classdefs", "src/parser/parser_prod.nit", 111);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_classdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 111);
+show_backtrace(1);
 }
 var15 = ((val* (*)(val*))(var14->class->vft[COLOR_abstract_collection__Collection__iterator]))(var14) /* iterator on <var14:ANodes[AClassdef]>*/;
 for(;;) {
@@ -627,24 +650,28 @@ if (var1){
 } else {
 }
 if (var_n_kwmodule == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 131);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 131);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AModuledecl___n_kwmodule].val = var_n_kwmodule; /* _n_kwmodule on <self:AModuledecl> */
 if (var_n_kwmodule == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 132);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 132);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwmodule->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwmodule, self) /* parent= on <var_n_kwmodule:nullable TKwmodule>*/;
 }
 if (var_n_name == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 133);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 133);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AModuledecl___n_name].val = var_n_name; /* _n_name on <self:AModuledecl> */
 if (var_n_name == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 134);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 134);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_name->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_name, self) /* parent= on <var_n_name:nullable AModuleName>*/;
 }
@@ -726,8 +753,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 146);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 146);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AModuledecl___n_doc].val = var_new_child; /* _n_doc on <self:AModuledecl> */
 } else {
@@ -739,8 +767,9 @@ goto RET_LABEL;
 }
 var6 = self->attrs[COLOR_parser_nodes__AModuledecl___n_kwmodule].val; /* _n_kwmodule on <self:AModuledecl> */
 if (var6 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwmodule", "src/parser/parser_prod.nit", 153);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwmodule");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 153);
+show_backtrace(1);
 }
 var7 = ((short int (*)(val*, val*))(var6->class->vft[COLOR_kernel__Object___61d_61d]))(var6, var_old_child) /* == on <var6:TKwmodule>*/;
 if (var7){
@@ -761,21 +790,24 @@ var10 = 0;
 var10 = var_new_child->type->type_table[cltype11] == idtype12;
 }
 if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 156);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 156);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AModuledecl___n_kwmodule].val = var_new_child; /* _n_kwmodule on <self:AModuledecl> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 159);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 159);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var13 = self->attrs[COLOR_parser_nodes__AModuledecl___n_name].val; /* _n_name on <self:AModuledecl> */
 if (var13 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_name", "src/parser/parser_prod.nit", 163);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_name");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 163);
+show_backtrace(1);
 }
 var14 = ((short int (*)(val*, val*))(var13->class->vft[COLOR_kernel__Object___61d_61d]))(var13, var_old_child) /* == on <var13:AModuleName>*/;
 if (var14){
@@ -796,13 +828,15 @@ var17 = 0;
 var17 = var_new_child->type->type_table[cltype18] == idtype19;
 }
 if (!var17) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 166);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 166);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AModuledecl___n_name].val = var_new_child; /* _n_name on <self:AModuledecl> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 169);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 169);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -831,8 +865,9 @@ var24 = 0;
 var24 = var_new_child->type->type_table[cltype25] == idtype26;
 }
 if (!var24) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 176);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 176);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:AModuledecl> */
 } else {
@@ -947,22 +982,25 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__AModuledecl___n_doc].val; /* _n_doc on <self:AModuledecl> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 214);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 214);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
 }
 var4 = self->attrs[COLOR_parser_nodes__AModuledecl___n_kwmodule].val; /* _n_kwmodule on <self:AModuledecl> */
 if (var4 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwmodule", "src/parser/parser_prod.nit", 216);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwmodule");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 216);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var4) /* enter_visit on <var_v:Visitor>*/;
 var5 = self->attrs[COLOR_parser_nodes__AModuledecl___n_name].val; /* _n_name on <self:AModuledecl> */
 if (var5 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_name", "src/parser/parser_prod.nit", 217);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_name");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 217);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var5) /* enter_visit on <var_v:Visitor>*/;
 var6 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AModuledecl> */
@@ -975,8 +1013,9 @@ var8 = 1; /* arg is null and recv is not */
 if (var8){
 var9 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AModuledecl> */
 if (var9 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 219);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 219);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var9) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -1011,35 +1050,41 @@ var_n_name = p2;
 var_n_annotations = p3;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AStdImport__empty_init]))(self) /* empty_init on <self:AStdImport>*/;
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 234);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 234);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdImport___n_visibility].val = var_n_visibility; /* _n_visibility on <self:AStdImport> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 235);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 235);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_kwimport == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 236);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 236);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdImport___n_kwimport].val = var_n_kwimport; /* _n_kwimport on <self:AStdImport> */
 if (var_n_kwimport == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 237);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 237);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwimport->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwimport, self) /* parent= on <var_n_kwimport:nullable TKwimport>*/;
 }
 if (var_n_name == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 238);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 238);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdImport___n_name].val = var_n_name; /* _n_name on <self:AStdImport> */
 if (var_n_name == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 239);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 239);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_name->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_name, self) /* parent= on <var_n_name:nullable AModuleName>*/;
 }
@@ -1098,8 +1143,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AStdImport___n_visibility].val; /* _n_visibility on <self:AStdImport> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_visibility", "src/parser/parser_prod.nit", 248);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_visibility");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 248);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:AVisibility>*/;
 if (var1){
@@ -1120,21 +1166,24 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 251);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 251);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdImport___n_visibility].val = var_new_child; /* _n_visibility on <self:AStdImport> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 254);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 254);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var5 = self->attrs[COLOR_parser_nodes__AStdImport___n_kwimport].val; /* _n_kwimport on <self:AStdImport> */
 if (var5 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwimport", "src/parser/parser_prod.nit", 258);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwimport");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 258);
+show_backtrace(1);
 }
 var6 = ((short int (*)(val*, val*))(var5->class->vft[COLOR_kernel__Object___61d_61d]))(var5, var_old_child) /* == on <var5:TKwimport>*/;
 if (var6){
@@ -1155,21 +1204,24 @@ var9 = 0;
 var9 = var_new_child->type->type_table[cltype10] == idtype11;
 }
 if (!var9) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 261);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 261);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdImport___n_kwimport].val = var_new_child; /* _n_kwimport on <self:AStdImport> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 264);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 264);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var12 = self->attrs[COLOR_parser_nodes__AStdImport___n_name].val; /* _n_name on <self:AStdImport> */
 if (var12 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_name", "src/parser/parser_prod.nit", 268);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_name");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 268);
+show_backtrace(1);
 }
 var13 = ((short int (*)(val*, val*))(var12->class->vft[COLOR_kernel__Object___61d_61d]))(var12, var_old_child) /* == on <var12:AModuleName>*/;
 if (var13){
@@ -1190,13 +1242,15 @@ var16 = 0;
 var16 = var_new_child->type->type_table[cltype17] == idtype18;
 }
 if (!var16) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 271);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 271);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdImport___n_name].val = var_new_child; /* _n_name on <self:AStdImport> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 274);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 274);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -1225,8 +1279,9 @@ var23 = 0;
 var23 = var_new_child->type->type_table[cltype24] == idtype25;
 }
 if (!var23) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 281);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 281);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:AStdImport> */
 } else {
@@ -1319,20 +1374,23 @@ val* var6 /* : nullable AAnnotations */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AStdImport___n_visibility].val; /* _n_visibility on <self:AStdImport> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_visibility", "src/parser/parser_prod.nit", 316);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_visibility");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 316);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 var1 = self->attrs[COLOR_parser_nodes__AStdImport___n_kwimport].val; /* _n_kwimport on <self:AStdImport> */
 if (var1 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwimport", "src/parser/parser_prod.nit", 317);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwimport");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 317);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var1) /* enter_visit on <var_v:Visitor>*/;
 var2 = self->attrs[COLOR_parser_nodes__AStdImport___n_name].val; /* _n_name on <self:AStdImport> */
 if (var2 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_name", "src/parser/parser_prod.nit", 318);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_name");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 318);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var2) /* enter_visit on <var_v:Visitor>*/;
 var3 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AStdImport> */
@@ -1345,8 +1403,9 @@ var5 = 1; /* arg is null and recv is not */
 if (var5){
 var6 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AStdImport> */
 if (var6 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 320);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 320);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var6) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -1377,35 +1436,41 @@ var_n_kwimport = p1;
 var_n_kwend = p2;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__ANoImport__empty_init]))(self) /* empty_init on <self:ANoImport>*/;
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 334);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 334);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ANoImport___n_visibility].val = var_n_visibility; /* _n_visibility on <self:ANoImport> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 335);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 335);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_kwimport == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 336);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 336);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ANoImport___n_kwimport].val = var_n_kwimport; /* _n_kwimport on <self:ANoImport> */
 if (var_n_kwimport == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 337);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 337);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwimport->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwimport, self) /* parent= on <var_n_kwimport:nullable TKwimport>*/;
 }
 if (var_n_kwend == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 338);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 338);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ANoImport___n_kwend].val = var_n_kwend; /* _n_kwend on <self:ANoImport> */
 if (var_n_kwend == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 339);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 339);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwend->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwend, self) /* parent= on <var_n_kwend:nullable TKwend>*/;
 }
@@ -1445,8 +1510,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__ANoImport___n_visibility].val; /* _n_visibility on <self:ANoImport> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_visibility", "src/parser/parser_prod.nit", 344);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_visibility");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 344);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:AVisibility>*/;
 if (var1){
@@ -1467,21 +1533,24 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 347);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 347);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ANoImport___n_visibility].val = var_new_child; /* _n_visibility on <self:ANoImport> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 350);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 350);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var5 = self->attrs[COLOR_parser_nodes__ANoImport___n_kwimport].val; /* _n_kwimport on <self:ANoImport> */
 if (var5 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwimport", "src/parser/parser_prod.nit", 354);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwimport");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 354);
+show_backtrace(1);
 }
 var6 = ((short int (*)(val*, val*))(var5->class->vft[COLOR_kernel__Object___61d_61d]))(var5, var_old_child) /* == on <var5:TKwimport>*/;
 if (var6){
@@ -1502,21 +1571,24 @@ var9 = 0;
 var9 = var_new_child->type->type_table[cltype10] == idtype11;
 }
 if (!var9) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 357);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 357);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ANoImport___n_kwimport].val = var_new_child; /* _n_kwimport on <self:ANoImport> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 360);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 360);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var12 = self->attrs[COLOR_parser_nodes__ANoImport___n_kwend].val; /* _n_kwend on <self:ANoImport> */
 if (var12 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwend", "src/parser/parser_prod.nit", 364);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwend");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 364);
+show_backtrace(1);
 }
 var13 = ((short int (*)(val*, val*))(var12->class->vft[COLOR_kernel__Object___61d_61d]))(var12, var_old_child) /* == on <var12:TKwend>*/;
 if (var13){
@@ -1537,13 +1609,15 @@ var16 = 0;
 var16 = var_new_child->type->type_table[cltype17] == idtype18;
 }
 if (!var16) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 367);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 367);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ANoImport___n_kwend].val = var_new_child; /* _n_kwend on <self:ANoImport> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 370);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 370);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -1603,20 +1677,23 @@ val* var2 /* : TKwend */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__ANoImport___n_visibility].val; /* _n_visibility on <self:ANoImport> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_visibility", "src/parser/parser_prod.nit", 395);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_visibility");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 395);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 var1 = self->attrs[COLOR_parser_nodes__ANoImport___n_kwimport].val; /* _n_kwimport on <self:ANoImport> */
 if (var1 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwimport", "src/parser/parser_prod.nit", 396);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwimport");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 396);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var1) /* enter_visit on <var_v:Visitor>*/;
 var2 = self->attrs[COLOR_parser_nodes__ANoImport___n_kwend].val; /* _n_kwend on <self:ANoImport> */
 if (var2 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwend", "src/parser/parser_prod.nit", 397);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwend");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 397);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var2) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -1684,13 +1761,15 @@ val* var_n_kwprivate /* var n_kwprivate: nullable TKwprivate */;
 var_n_kwprivate = p0;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__APrivateVisibility__empty_init]))(self) /* empty_init on <self:APrivateVisibility>*/;
 if (var_n_kwprivate == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 426);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 426);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__APrivateVisibility___n_kwprivate].val = var_n_kwprivate; /* _n_kwprivate on <self:APrivateVisibility> */
 if (var_n_kwprivate == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 427);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 427);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwprivate->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwprivate, self) /* parent= on <var_n_kwprivate:nullable TKwprivate>*/;
 }
@@ -1716,8 +1795,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__APrivateVisibility___n_kwprivate].val; /* _n_kwprivate on <self:APrivateVisibility> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwprivate", "src/parser/parser_prod.nit", 432);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwprivate");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 432);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwprivate>*/;
 if (var1){
@@ -1738,13 +1818,15 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 435);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 435);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__APrivateVisibility___n_kwprivate].val = var_new_child; /* _n_kwprivate on <self:APrivateVisibility> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 438);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 438);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -1776,8 +1858,9 @@ val* var /* : TKwprivate */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__APrivateVisibility___n_kwprivate].val; /* _n_kwprivate on <self:APrivateVisibility> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwprivate", "src/parser/parser_prod.nit", 453);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwprivate");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 453);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -1802,13 +1885,15 @@ val* var_n_kwprotected /* var n_kwprotected: nullable TKwprotected */;
 var_n_kwprotected = p0;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AProtectedVisibility__empty_init]))(self) /* empty_init on <self:AProtectedVisibility>*/;
 if (var_n_kwprotected == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 464);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 464);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AProtectedVisibility___n_kwprotected].val = var_n_kwprotected; /* _n_kwprotected on <self:AProtectedVisibility> */
 if (var_n_kwprotected == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 465);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 465);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwprotected->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwprotected, self) /* parent= on <var_n_kwprotected:nullable TKwprotected>*/;
 }
@@ -1834,8 +1919,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AProtectedVisibility___n_kwprotected].val; /* _n_kwprotected on <self:AProtectedVisibility> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwprotected", "src/parser/parser_prod.nit", 470);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwprotected");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 470);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwprotected>*/;
 if (var1){
@@ -1856,13 +1942,15 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 473);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 473);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AProtectedVisibility___n_kwprotected].val = var_new_child; /* _n_kwprotected on <self:AProtectedVisibility> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 476);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 476);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -1894,8 +1982,9 @@ val* var /* : TKwprotected */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AProtectedVisibility___n_kwprotected].val; /* _n_kwprotected on <self:AProtectedVisibility> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwprotected", "src/parser/parser_prod.nit", 491);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwprotected");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 491);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -1920,13 +2009,15 @@ val* var_n_kwintrude /* var n_kwintrude: nullable TKwintrude */;
 var_n_kwintrude = p0;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AIntrudeVisibility__empty_init]))(self) /* empty_init on <self:AIntrudeVisibility>*/;
 if (var_n_kwintrude == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 502);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 502);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AIntrudeVisibility___n_kwintrude].val = var_n_kwintrude; /* _n_kwintrude on <self:AIntrudeVisibility> */
 if (var_n_kwintrude == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 503);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 503);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwintrude->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwintrude, self) /* parent= on <var_n_kwintrude:nullable TKwintrude>*/;
 }
@@ -1952,8 +2043,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AIntrudeVisibility___n_kwintrude].val; /* _n_kwintrude on <self:AIntrudeVisibility> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwintrude", "src/parser/parser_prod.nit", 508);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwintrude");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 508);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwintrude>*/;
 if (var1){
@@ -1974,13 +2066,15 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 511);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 511);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AIntrudeVisibility___n_kwintrude].val = var_new_child; /* _n_kwintrude on <self:AIntrudeVisibility> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 514);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 514);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -2012,8 +2106,9 @@ val* var /* : TKwintrude */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AIntrudeVisibility___n_kwintrude].val; /* _n_kwintrude on <self:AIntrudeVisibility> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwintrude", "src/parser/parser_prod.nit", 529);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwintrude");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 529);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -2114,24 +2209,28 @@ if (var3){
 } else {
 }
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 558);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 558);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_visibility].val = var_n_visibility; /* _n_visibility on <self:AStdClassdef> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 559);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 559);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_classkind == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 560);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 560);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_classkind].val = var_n_classkind; /* _n_classkind on <self:AStdClassdef> */
 if (var_n_classkind == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 561);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 561);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_classkind->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_classkind, self) /* parent= on <var_n_classkind:nullable AClasskind>*/;
 }
@@ -2161,13 +2260,15 @@ var9 = 0;
 var9 = var_n->type->type_table[cltype] == idtype;
 }
 if (!var9) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 567);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 567);
+show_backtrace(1);
 }
 var10 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_formaldefs].val; /* _n_formaldefs on <self:AStdClassdef> */
 if (var10 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_formaldefs", "src/parser/parser_prod.nit", 568);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_formaldefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 568);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var10->class->vft[COLOR_abstract_collection__SimpleCollection__add]))(var10, var_n) /* add on <var10:ANodes[AFormaldef]>*/;
 ((void (*)(val*, val*))(var_n->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n, self) /* parent= on <var_n:Object(AFormaldef)>*/;
@@ -2212,13 +2313,15 @@ var19 = 0;
 var19 = var_n18->type->type_table[cltype20] == idtype21;
 }
 if (!var19) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 580);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 580);
+show_backtrace(1);
 }
 var22 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_superclasses].val; /* _n_superclasses on <self:AStdClassdef> */
 if (var22 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_superclasses", "src/parser/parser_prod.nit", 581);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_superclasses");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 581);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var22->class->vft[COLOR_abstract_collection__SimpleCollection__add]))(var22, var_n18) /* add on <var22:ANodes[ASuperclass]>*/;
 ((void (*)(val*, val*))(var_n18->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n18, self) /* parent= on <var_n18:Object(ASuperclass)>*/;
@@ -2241,13 +2344,15 @@ var28 = 0;
 var28 = var_n27->type->type_table[cltype29] == idtype30;
 }
 if (!var28) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 585);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 585);
+show_backtrace(1);
 }
 var31 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AStdClassdef> */
 if (var31 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 586);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 586);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var31->class->vft[COLOR_abstract_collection__SimpleCollection__add]))(var31, var_n27) /* add on <var31:ANodes[APropdef]>*/;
 ((void (*)(val*, val*))(var_n27->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n27, self) /* parent= on <var_n27:Object(APropdef)>*/;
@@ -2256,13 +2361,15 @@ CONTINUE_label32: (void)0;
 }
 BREAK_label32: (void)0;
 if (var_n_kwend == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 589);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 589);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_kwend].val = var_n_kwend; /* _n_kwend on <self:AStdClassdef> */
 if (var_n_kwend == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 590);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 590);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwend->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwend, self) /* parent= on <var_n_kwend:nullable TKwend>*/;
 }
@@ -2427,8 +2534,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 598);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 598);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_doc].val = var_new_child; /* _n_doc on <self:AStdClassdef> */
 } else {
@@ -2462,8 +2570,9 @@ var10 = 0;
 var10 = var_new_child->type->type_table[cltype11] == idtype12;
 }
 if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 608);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 608);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_kwredef].val = var_new_child; /* _n_kwredef on <self:AStdClassdef> */
 } else {
@@ -2475,8 +2584,9 @@ goto RET_LABEL;
 }
 var14 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_visibility].val; /* _n_visibility on <self:AStdClassdef> */
 if (var14 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_visibility", "src/parser/parser_prod.nit", 615);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_visibility");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 615);
+show_backtrace(1);
 }
 var15 = ((short int (*)(val*, val*))(var14->class->vft[COLOR_kernel__Object___61d_61d]))(var14, var_old_child) /* == on <var14:AVisibility>*/;
 if (var15){
@@ -2497,21 +2607,24 @@ var18 = 0;
 var18 = var_new_child->type->type_table[cltype19] == idtype20;
 }
 if (!var18) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 618);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 618);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_visibility].val = var_new_child; /* _n_visibility on <self:AStdClassdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 621);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 621);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var21 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_classkind].val; /* _n_classkind on <self:AStdClassdef> */
 if (var21 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_classkind", "src/parser/parser_prod.nit", 625);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_classkind");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 625);
+show_backtrace(1);
 }
 var22 = ((short int (*)(val*, val*))(var21->class->vft[COLOR_kernel__Object___61d_61d]))(var21, var_old_child) /* == on <var21:AClasskind>*/;
 if (var22){
@@ -2532,13 +2645,15 @@ var25 = 0;
 var25 = var_new_child->type->type_table[cltype26] == idtype27;
 }
 if (!var25) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 628);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 628);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_classkind].val = var_new_child; /* _n_classkind on <self:AStdClassdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 631);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 631);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -2567,8 +2682,9 @@ var32 = 0;
 var32 = var_new_child->type->type_table[cltype33] == idtype34;
 }
 if (!var32) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 638);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 638);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_id].val = var_new_child; /* _n_id on <self:AStdClassdef> */
 } else {
@@ -2582,14 +2698,14 @@ var36 = NEW_range__Range(&type_range__Rangekernel__Int);
 var37 = 0;
 var38 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_formaldefs].val; /* _n_formaldefs on <self:AStdClassdef> */
 if (var38 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_formaldefs", "src/parser/parser_prod.nit", 645);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_formaldefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 645);
+show_backtrace(1);
 }
 var39 = ((long (*)(val*))(var38->class->vft[COLOR_abstract_collection__Collection__length]))(var38) /* length on <var38:ANodes[AFormaldef]>*/;
 var40 = BOX_kernel__Int(var37); /* autobox from Int to Discrete */
 var41 = BOX_kernel__Int(var39); /* autobox from Int to Discrete */
 ((void (*)(val*, val*, val*))(var36->class->vft[COLOR_range__Range__without_last]))(var36, var40, var41) /* without_last on <var36:Range[Int]>*/;
-CHECK_NEW_range__Range(var36);
 var42 = ((val* (*)(val*))(var36->class->vft[COLOR_abstract_collection__Collection__iterator]))(var36) /* iterator on <var36:Range[Int]>*/;
 for(;;) {
 var43 = ((short int (*)(val*))(var42->class->vft[COLOR_abstract_collection__Iterator__is_ok]))(var42) /* is_ok on <var42:Iterator[nullable Object]>*/;
@@ -2599,8 +2715,9 @@ var45 = ((struct instance_kernel__Int*)var44)->value; /* autounbox from nullable
 var_i = var45;
 var46 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_formaldefs].val; /* _n_formaldefs on <self:AStdClassdef> */
 if (var46 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_formaldefs", "src/parser/parser_prod.nit", 646);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_formaldefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 646);
+show_backtrace(1);
 }
 var47 = ((val* (*)(val*, long))(var46->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var46, var_i) /* [] on <var46:ANodes[AFormaldef]>*/;
 var48 = ((short int (*)(val*, val*))(var47->class->vft[COLOR_kernel__Object___61d_61d]))(var47, var_old_child) /* == on <var47:nullable Object(AFormaldef)>*/;
@@ -2621,21 +2738,24 @@ var51 = 0;
 var51 = var_new_child->type->type_table[cltype52] == idtype53;
 }
 if (!var51) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 648);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 648);
+show_backtrace(1);
 }
 var54 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_formaldefs].val; /* _n_formaldefs on <self:AStdClassdef> */
 if (var54 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_formaldefs", "src/parser/parser_prod.nit", 649);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_formaldefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 649);
+show_backtrace(1);
 }
 ((void (*)(val*, long, val*))(var54->class->vft[COLOR_abstract_collection__Sequence___91d_93d_61d]))(var54, var_i, var_new_child) /* []= on <var54:ANodes[AFormaldef]>*/;
 ((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(AFormaldef)>*/;
 } else {
 var55 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_formaldefs].val; /* _n_formaldefs on <self:AStdClassdef> */
 if (var55 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_formaldefs", "src/parser/parser_prod.nit", 652);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_formaldefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 652);
+show_backtrace(1);
 }
 ((void (*)(val*, long))(var55->class->vft[COLOR_abstract_collection__Sequence__remove_at]))(var55, var_i) /* remove_at on <var55:ANodes[AFormaldef]>*/;
 }
@@ -2670,8 +2790,9 @@ var60 = 0;
 var60 = var_new_child->type->type_table[cltype61] == idtype62;
 }
 if (!var60) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 660);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 660);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:AStdClassdef> */
 } else {
@@ -2705,8 +2826,9 @@ var68 = 0;
 var68 = var_new_child->type->type_table[cltype69] == idtype70;
 }
 if (!var68) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 670);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 670);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_extern_code_block].val = var_new_child; /* _n_extern_code_block on <self:AStdClassdef> */
 } else {
@@ -2720,14 +2842,14 @@ var72 = NEW_range__Range(&type_range__Rangekernel__Int);
 var73 = 0;
 var74 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_superclasses].val; /* _n_superclasses on <self:AStdClassdef> */
 if (var74 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_superclasses", "src/parser/parser_prod.nit", 677);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_superclasses");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 677);
+show_backtrace(1);
 }
 var75 = ((long (*)(val*))(var74->class->vft[COLOR_abstract_collection__Collection__length]))(var74) /* length on <var74:ANodes[ASuperclass]>*/;
 var76 = BOX_kernel__Int(var73); /* autobox from Int to Discrete */
 var77 = BOX_kernel__Int(var75); /* autobox from Int to Discrete */
 ((void (*)(val*, val*, val*))(var72->class->vft[COLOR_range__Range__without_last]))(var72, var76, var77) /* without_last on <var72:Range[Int]>*/;
-CHECK_NEW_range__Range(var72);
 var78 = ((val* (*)(val*))(var72->class->vft[COLOR_abstract_collection__Collection__iterator]))(var72) /* iterator on <var72:Range[Int]>*/;
 for(;;) {
 var79 = ((short int (*)(val*))(var78->class->vft[COLOR_abstract_collection__Iterator__is_ok]))(var78) /* is_ok on <var78:Iterator[nullable Object]>*/;
@@ -2737,8 +2859,9 @@ var82 = ((struct instance_kernel__Int*)var80)->value; /* autounbox from nullable
 var_i81 = var82;
 var83 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_superclasses].val; /* _n_superclasses on <self:AStdClassdef> */
 if (var83 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_superclasses", "src/parser/parser_prod.nit", 678);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_superclasses");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 678);
+show_backtrace(1);
 }
 var84 = ((val* (*)(val*, long))(var83->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var83, var_i81) /* [] on <var83:ANodes[ASuperclass]>*/;
 var85 = ((short int (*)(val*, val*))(var84->class->vft[COLOR_kernel__Object___61d_61d]))(var84, var_old_child) /* == on <var84:nullable Object(ASuperclass)>*/;
@@ -2759,21 +2882,24 @@ var88 = 0;
 var88 = var_new_child->type->type_table[cltype89] == idtype90;
 }
 if (!var88) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 680);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 680);
+show_backtrace(1);
 }
 var91 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_superclasses].val; /* _n_superclasses on <self:AStdClassdef> */
 if (var91 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_superclasses", "src/parser/parser_prod.nit", 681);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_superclasses");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 681);
+show_backtrace(1);
 }
 ((void (*)(val*, long, val*))(var91->class->vft[COLOR_abstract_collection__Sequence___91d_93d_61d]))(var91, var_i81, var_new_child) /* []= on <var91:ANodes[ASuperclass]>*/;
 ((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ASuperclass)>*/;
 } else {
 var92 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_superclasses].val; /* _n_superclasses on <self:AStdClassdef> */
 if (var92 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_superclasses", "src/parser/parser_prod.nit", 684);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_superclasses");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 684);
+show_backtrace(1);
 }
 ((void (*)(val*, long))(var92->class->vft[COLOR_abstract_collection__Sequence__remove_at]))(var92, var_i81) /* remove_at on <var92:ANodes[ASuperclass]>*/;
 }
@@ -2788,14 +2914,14 @@ var94 = NEW_range__Range(&type_range__Rangekernel__Int);
 var95 = 0;
 var96 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AStdClassdef> */
 if (var96 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 689);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 689);
+show_backtrace(1);
 }
 var97 = ((long (*)(val*))(var96->class->vft[COLOR_abstract_collection__Collection__length]))(var96) /* length on <var96:ANodes[APropdef]>*/;
 var98 = BOX_kernel__Int(var95); /* autobox from Int to Discrete */
 var99 = BOX_kernel__Int(var97); /* autobox from Int to Discrete */
 ((void (*)(val*, val*, val*))(var94->class->vft[COLOR_range__Range__without_last]))(var94, var98, var99) /* without_last on <var94:Range[Int]>*/;
-CHECK_NEW_range__Range(var94);
 var100 = ((val* (*)(val*))(var94->class->vft[COLOR_abstract_collection__Collection__iterator]))(var94) /* iterator on <var94:Range[Int]>*/;
 for(;;) {
 var101 = ((short int (*)(val*))(var100->class->vft[COLOR_abstract_collection__Iterator__is_ok]))(var100) /* is_ok on <var100:Iterator[nullable Object]>*/;
@@ -2805,8 +2931,9 @@ var104 = ((struct instance_kernel__Int*)var102)->value; /* autounbox from nullab
 var_i103 = var104;
 var105 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AStdClassdef> */
 if (var105 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 690);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 690);
+show_backtrace(1);
 }
 var106 = ((val* (*)(val*, long))(var105->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var105, var_i103) /* [] on <var105:ANodes[APropdef]>*/;
 var107 = ((short int (*)(val*, val*))(var106->class->vft[COLOR_kernel__Object___61d_61d]))(var106, var_old_child) /* == on <var106:nullable Object(APropdef)>*/;
@@ -2827,21 +2954,24 @@ var110 = 0;
 var110 = var_new_child->type->type_table[cltype111] == idtype112;
 }
 if (!var110) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 692);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 692);
+show_backtrace(1);
 }
 var113 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AStdClassdef> */
 if (var113 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 693);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 693);
+show_backtrace(1);
 }
 ((void (*)(val*, long, val*))(var113->class->vft[COLOR_abstract_collection__Sequence___91d_93d_61d]))(var113, var_i103, var_new_child) /* []= on <var113:ANodes[APropdef]>*/;
 ((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(APropdef)>*/;
 } else {
 var114 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AStdClassdef> */
 if (var114 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 696);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 696);
+show_backtrace(1);
 }
 ((void (*)(val*, long))(var114->class->vft[COLOR_abstract_collection__Sequence__remove_at]))(var114, var_i103) /* remove_at on <var114:ANodes[APropdef]>*/;
 }
@@ -2854,8 +2984,9 @@ CONTINUE_label115: (void)0;
 BREAK_label115: (void)0;
 var116 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_kwend].val; /* _n_kwend on <self:AStdClassdef> */
 if (var116 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwend", "src/parser/parser_prod.nit", 701);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwend");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 701);
+show_backtrace(1);
 }
 var117 = ((short int (*)(val*, val*))(var116->class->vft[COLOR_kernel__Object___61d_61d]))(var116, var_old_child) /* == on <var116:TKwend>*/;
 if (var117){
@@ -2876,13 +3007,15 @@ var120 = 0;
 var120 = var_new_child->type->type_table[cltype121] == idtype122;
 }
 if (!var120) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 704);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 704);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AStdClassdef___n_kwend].val = var_new_child; /* _n_kwend on <self:AStdClassdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 707);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 707);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -3105,8 +3238,9 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_doc].val; /* _n_doc on <self:AStdClassdef> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 768);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 768);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -3121,22 +3255,25 @@ var6 = 1; /* arg is null and recv is not */
 if (var6){
 var7 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_kwredef].val; /* _n_kwredef on <self:AStdClassdef> */
 if (var7 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 771);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 771);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var7) /* enter_visit on <var_v:Visitor>*/;
 } else {
 }
 var8 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_visibility].val; /* _n_visibility on <self:AStdClassdef> */
 if (var8 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_visibility", "src/parser/parser_prod.nit", 773);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_visibility");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 773);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var8) /* enter_visit on <var_v:Visitor>*/;
 var9 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_classkind].val; /* _n_classkind on <self:AStdClassdef> */
 if (var9 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_classkind", "src/parser/parser_prod.nit", 774);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_classkind");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 774);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var9) /* enter_visit on <var_v:Visitor>*/;
 var10 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_id].val; /* _n_id on <self:AStdClassdef> */
@@ -3149,16 +3286,18 @@ var12 = 1; /* arg is null and recv is not */
 if (var12){
 var13 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_id].val; /* _n_id on <self:AStdClassdef> */
 if (var13 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 776);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 776);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var13) /* enter_visit on <var_v:Visitor>*/;
 } else {
 }
 var14 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_formaldefs].val; /* _n_formaldefs on <self:AStdClassdef> */
 if (var14 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_formaldefs", "src/parser/parser_prod.nit", 778);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_formaldefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 778);
+show_backtrace(1);
 }
 var15 = ((val* (*)(val*))(var14->class->vft[COLOR_abstract_collection__Collection__iterator]))(var14) /* iterator on <var14:ANodes[AFormaldef]>*/;
 for(;;) {
@@ -3181,8 +3320,9 @@ var20 = 1; /* arg is null and recv is not */
 if (var20){
 var21 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AStdClassdef> */
 if (var21 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 782);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 782);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var21) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -3197,16 +3337,18 @@ var24 = 1; /* arg is null and recv is not */
 if (var24){
 var25 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_extern_code_block].val; /* _n_extern_code_block on <self:AStdClassdef> */
 if (var25 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 785);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 785);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var25) /* enter_visit on <var_v:Visitor>*/;
 } else {
 }
 var26 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_superclasses].val; /* _n_superclasses on <self:AStdClassdef> */
 if (var26 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_superclasses", "src/parser/parser_prod.nit", 787);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_superclasses");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 787);
+show_backtrace(1);
 }
 var27 = ((val* (*)(val*))(var26->class->vft[COLOR_abstract_collection__Collection__iterator]))(var26) /* iterator on <var26:ANodes[ASuperclass]>*/;
 for(;;) {
@@ -3221,8 +3363,9 @@ CONTINUE_label31: (void)0;
 BREAK_label31: (void)0;
 var32 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AStdClassdef> */
 if (var32 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 790);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 790);
+show_backtrace(1);
 }
 var33 = ((val* (*)(val*))(var32->class->vft[COLOR_abstract_collection__Collection__iterator]))(var32) /* iterator on <var32:ANodes[APropdef]>*/;
 for(;;) {
@@ -3237,8 +3380,9 @@ CONTINUE_label37: (void)0;
 BREAK_label37: (void)0;
 var38 = self->attrs[COLOR_parser_nodes__AStdClassdef___n_kwend].val; /* _n_kwend on <self:AStdClassdef> */
 if (var38 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwend", "src/parser/parser_prod.nit", 793);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwend");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 793);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var38) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -3285,13 +3429,15 @@ var3 = 0;
 var3 = var_n->type->type_table[cltype] == idtype;
 }
 if (!var3) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 805);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 805);
+show_backtrace(1);
 }
 var4 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:ATopClassdef> */
 if (var4 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 806);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 806);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var4->class->vft[COLOR_abstract_collection__SimpleCollection__add]))(var4, var_n) /* add on <var4:ANodes[APropdef]>*/;
 ((void (*)(val*, val*))(var_n->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n, self) /* parent= on <var_n:Object(APropdef)>*/;
@@ -3337,14 +3483,14 @@ var = NEW_range__Range(&type_range__Rangekernel__Int);
 var1 = 0;
 var2 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:ATopClassdef> */
 if (var2 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 813);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 813);
+show_backtrace(1);
 }
 var3 = ((long (*)(val*))(var2->class->vft[COLOR_abstract_collection__Collection__length]))(var2) /* length on <var2:ANodes[APropdef]>*/;
 var4 = BOX_kernel__Int(var1); /* autobox from Int to Discrete */
 var5 = BOX_kernel__Int(var3); /* autobox from Int to Discrete */
 ((void (*)(val*, val*, val*))(var->class->vft[COLOR_range__Range__without_last]))(var, var4, var5) /* without_last on <var:Range[Int]>*/;
-CHECK_NEW_range__Range(var);
 var6 = ((val* (*)(val*))(var->class->vft[COLOR_abstract_collection__Collection__iterator]))(var) /* iterator on <var:Range[Int]>*/;
 for(;;) {
 var7 = ((short int (*)(val*))(var6->class->vft[COLOR_abstract_collection__Iterator__is_ok]))(var6) /* is_ok on <var6:Iterator[nullable Object]>*/;
@@ -3354,8 +3500,9 @@ var9 = ((struct instance_kernel__Int*)var8)->value; /* autounbox from nullable O
 var_i = var9;
 var10 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:ATopClassdef> */
 if (var10 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 814);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 814);
+show_backtrace(1);
 }
 var11 = ((val* (*)(val*, long))(var10->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var10, var_i) /* [] on <var10:ANodes[APropdef]>*/;
 var12 = ((short int (*)(val*, val*))(var11->class->vft[COLOR_kernel__Object___61d_61d]))(var11, var_old_child) /* == on <var11:nullable Object(APropdef)>*/;
@@ -3376,21 +3523,24 @@ var15 = 0;
 var15 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var15) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 816);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 816);
+show_backtrace(1);
 }
 var16 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:ATopClassdef> */
 if (var16 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 817);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 817);
+show_backtrace(1);
 }
 ((void (*)(val*, long, val*))(var16->class->vft[COLOR_abstract_collection__Sequence___91d_93d_61d]))(var16, var_i, var_new_child) /* []= on <var16:ANodes[APropdef]>*/;
 ((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(APropdef)>*/;
 } else {
 var17 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:ATopClassdef> */
 if (var17 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 820);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 820);
+show_backtrace(1);
 }
 ((void (*)(val*, long))(var17->class->vft[COLOR_abstract_collection__Sequence__remove_at]))(var17, var_i) /* remove_at on <var17:ANodes[APropdef]>*/;
 }
@@ -3419,8 +3569,9 @@ val* var_n /* var n: APropdef */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:ATopClassdef> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 831);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 831);
+show_backtrace(1);
 }
 var1 = ((val* (*)(val*))(var->class->vft[COLOR_abstract_collection__Collection__iterator]))(var) /* iterator on <var:ANodes[APropdef]>*/;
 for(;;) {
@@ -3477,13 +3628,15 @@ var3 = 0;
 var3 = var_n->type->type_table[cltype] == idtype;
 }
 if (!var3) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 845);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 845);
+show_backtrace(1);
 }
 var4 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AMainClassdef> */
 if (var4 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 846);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 846);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var4->class->vft[COLOR_abstract_collection__SimpleCollection__add]))(var4, var_n) /* add on <var4:ANodes[APropdef]>*/;
 ((void (*)(val*, val*))(var_n->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n, self) /* parent= on <var_n:Object(APropdef)>*/;
@@ -3529,14 +3682,14 @@ var = NEW_range__Range(&type_range__Rangekernel__Int);
 var1 = 0;
 var2 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AMainClassdef> */
 if (var2 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 853);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 853);
+show_backtrace(1);
 }
 var3 = ((long (*)(val*))(var2->class->vft[COLOR_abstract_collection__Collection__length]))(var2) /* length on <var2:ANodes[APropdef]>*/;
 var4 = BOX_kernel__Int(var1); /* autobox from Int to Discrete */
 var5 = BOX_kernel__Int(var3); /* autobox from Int to Discrete */
 ((void (*)(val*, val*, val*))(var->class->vft[COLOR_range__Range__without_last]))(var, var4, var5) /* without_last on <var:Range[Int]>*/;
-CHECK_NEW_range__Range(var);
 var6 = ((val* (*)(val*))(var->class->vft[COLOR_abstract_collection__Collection__iterator]))(var) /* iterator on <var:Range[Int]>*/;
 for(;;) {
 var7 = ((short int (*)(val*))(var6->class->vft[COLOR_abstract_collection__Iterator__is_ok]))(var6) /* is_ok on <var6:Iterator[nullable Object]>*/;
@@ -3546,8 +3699,9 @@ var9 = ((struct instance_kernel__Int*)var8)->value; /* autounbox from nullable O
 var_i = var9;
 var10 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AMainClassdef> */
 if (var10 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 854);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 854);
+show_backtrace(1);
 }
 var11 = ((val* (*)(val*, long))(var10->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var10, var_i) /* [] on <var10:ANodes[APropdef]>*/;
 var12 = ((short int (*)(val*, val*))(var11->class->vft[COLOR_kernel__Object___61d_61d]))(var11, var_old_child) /* == on <var11:nullable Object(APropdef)>*/;
@@ -3568,21 +3722,24 @@ var15 = 0;
 var15 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var15) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 856);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 856);
+show_backtrace(1);
 }
 var16 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AMainClassdef> */
 if (var16 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 857);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 857);
+show_backtrace(1);
 }
 ((void (*)(val*, long, val*))(var16->class->vft[COLOR_abstract_collection__Sequence___91d_93d_61d]))(var16, var_i, var_new_child) /* []= on <var16:ANodes[APropdef]>*/;
 ((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(APropdef)>*/;
 } else {
 var17 = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AMainClassdef> */
 if (var17 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 860);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 860);
+show_backtrace(1);
 }
 ((void (*)(val*, long))(var17->class->vft[COLOR_abstract_collection__Sequence__remove_at]))(var17, var_i) /* remove_at on <var17:ANodes[APropdef]>*/;
 }
@@ -3611,8 +3768,9 @@ val* var_n /* var n: APropdef */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AClassdef___n_propdefs].val; /* _n_propdefs on <self:AMainClassdef> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_propdefs", "src/parser/parser_prod.nit", 871);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_propdefs");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 871);
+show_backtrace(1);
 }
 var1 = ((val* (*)(val*))(var->class->vft[COLOR_abstract_collection__Collection__iterator]))(var) /* iterator on <var:ANodes[APropdef]>*/;
 for(;;) {
@@ -3647,13 +3805,15 @@ val* var_n_kwclass /* var n_kwclass: nullable TKwclass */;
 var_n_kwclass = p0;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AConcreteClasskind__empty_init]))(self) /* empty_init on <self:AConcreteClasskind>*/;
 if (var_n_kwclass == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 884);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 884);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AConcreteClasskind___n_kwclass].val = var_n_kwclass; /* _n_kwclass on <self:AConcreteClasskind> */
 if (var_n_kwclass == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 885);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 885);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwclass->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwclass, self) /* parent= on <var_n_kwclass:nullable TKwclass>*/;
 }
@@ -3679,8 +3839,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AConcreteClasskind___n_kwclass].val; /* _n_kwclass on <self:AConcreteClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwclass", "src/parser/parser_prod.nit", 890);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwclass");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 890);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwclass>*/;
 if (var1){
@@ -3701,13 +3862,15 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 893);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 893);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AConcreteClasskind___n_kwclass].val = var_new_child; /* _n_kwclass on <self:AConcreteClasskind> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 896);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 896);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -3739,8 +3902,9 @@ val* var /* : TKwclass */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AConcreteClasskind___n_kwclass].val; /* _n_kwclass on <self:AConcreteClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwclass", "src/parser/parser_prod.nit", 911);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwclass");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 911);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -3767,24 +3931,28 @@ var_n_kwabstract = p0;
 var_n_kwclass = p1;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AAbstractClasskind__empty_init]))(self) /* empty_init on <self:AAbstractClasskind>*/;
 if (var_n_kwabstract == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 923);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 923);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAbstractClasskind___n_kwabstract].val = var_n_kwabstract; /* _n_kwabstract on <self:AAbstractClasskind> */
 if (var_n_kwabstract == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 924);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 924);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwabstract->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwabstract, self) /* parent= on <var_n_kwabstract:nullable TKwabstract>*/;
 }
 if (var_n_kwclass == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 925);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 925);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAbstractClasskind___n_kwclass].val = var_n_kwclass; /* _n_kwclass on <self:AAbstractClasskind> */
 if (var_n_kwclass == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 926);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 926);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwclass->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwclass, self) /* parent= on <var_n_kwclass:nullable TKwclass>*/;
 }
@@ -3817,8 +3985,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AAbstractClasskind___n_kwabstract].val; /* _n_kwabstract on <self:AAbstractClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwabstract", "src/parser/parser_prod.nit", 931);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwabstract");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 931);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwabstract>*/;
 if (var1){
@@ -3839,21 +4008,24 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 934);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 934);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAbstractClasskind___n_kwabstract].val = var_new_child; /* _n_kwabstract on <self:AAbstractClasskind> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 937);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 937);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var5 = self->attrs[COLOR_parser_nodes__AAbstractClasskind___n_kwclass].val; /* _n_kwclass on <self:AAbstractClasskind> */
 if (var5 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwclass", "src/parser/parser_prod.nit", 941);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwclass");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 941);
+show_backtrace(1);
 }
 var6 = ((short int (*)(val*, val*))(var5->class->vft[COLOR_kernel__Object___61d_61d]))(var5, var_old_child) /* == on <var5:TKwclass>*/;
 if (var6){
@@ -3874,13 +4046,15 @@ var9 = 0;
 var9 = var_new_child->type->type_table[cltype10] == idtype11;
 }
 if (!var9) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 944);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 944);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAbstractClasskind___n_kwclass].val = var_new_child; /* _n_kwclass on <self:AAbstractClasskind> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 947);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 947);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -3926,14 +4100,16 @@ val* var1 /* : TKwclass */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AAbstractClasskind___n_kwabstract].val; /* _n_kwabstract on <self:AAbstractClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwabstract", "src/parser/parser_prod.nit", 967);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwabstract");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 967);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 var1 = self->attrs[COLOR_parser_nodes__AAbstractClasskind___n_kwclass].val; /* _n_kwclass on <self:AAbstractClasskind> */
 if (var1 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwclass", "src/parser/parser_prod.nit", 968);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwclass");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 968);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var1) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -3958,13 +4134,15 @@ val* var_n_kwinterface /* var n_kwinterface: nullable TKwinterface */;
 var_n_kwinterface = p0;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AInterfaceClasskind__empty_init]))(self) /* empty_init on <self:AInterfaceClasskind>*/;
 if (var_n_kwinterface == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 979);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 979);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AInterfaceClasskind___n_kwinterface].val = var_n_kwinterface; /* _n_kwinterface on <self:AInterfaceClasskind> */
 if (var_n_kwinterface == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 980);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 980);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwinterface->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwinterface, self) /* parent= on <var_n_kwinterface:nullable TKwinterface>*/;
 }
@@ -3990,8 +4168,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AInterfaceClasskind___n_kwinterface].val; /* _n_kwinterface on <self:AInterfaceClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwinterface", "src/parser/parser_prod.nit", 985);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwinterface");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 985);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwinterface>*/;
 if (var1){
@@ -4012,13 +4191,15 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 988);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 988);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AInterfaceClasskind___n_kwinterface].val = var_new_child; /* _n_kwinterface on <self:AInterfaceClasskind> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 991);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 991);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -4050,8 +4231,9 @@ val* var /* : TKwinterface */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AInterfaceClasskind___n_kwinterface].val; /* _n_kwinterface on <self:AInterfaceClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwinterface", "src/parser/parser_prod.nit", 1006);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwinterface");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1006);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -4076,13 +4258,15 @@ val* var_n_kwenum /* var n_kwenum: nullable TKwenum */;
 var_n_kwenum = p0;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AEnumClasskind__empty_init]))(self) /* empty_init on <self:AEnumClasskind>*/;
 if (var_n_kwenum == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1017);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1017);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AEnumClasskind___n_kwenum].val = var_n_kwenum; /* _n_kwenum on <self:AEnumClasskind> */
 if (var_n_kwenum == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1018);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1018);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwenum->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwenum, self) /* parent= on <var_n_kwenum:nullable TKwenum>*/;
 }
@@ -4108,8 +4292,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AEnumClasskind___n_kwenum].val; /* _n_kwenum on <self:AEnumClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwenum", "src/parser/parser_prod.nit", 1023);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwenum");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1023);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwenum>*/;
 if (var1){
@@ -4130,13 +4315,15 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1026);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1026);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AEnumClasskind___n_kwenum].val = var_new_child; /* _n_kwenum on <self:AEnumClasskind> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1029);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1029);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -4168,8 +4355,9 @@ val* var /* : TKwenum */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AEnumClasskind___n_kwenum].val; /* _n_kwenum on <self:AEnumClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwenum", "src/parser/parser_prod.nit", 1044);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwenum");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1044);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 RET_LABEL:;
@@ -4198,13 +4386,15 @@ var_n_kwextern = p0;
 var_n_kwclass = p1;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AExternClasskind__empty_init]))(self) /* empty_init on <self:AExternClasskind>*/;
 if (var_n_kwextern == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1056);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1056);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AExternClasskind___n_kwextern].val = var_n_kwextern; /* _n_kwextern on <self:AExternClasskind> */
 if (var_n_kwextern == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1057);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1057);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwextern->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwextern, self) /* parent= on <var_n_kwextern:nullable TKwextern>*/;
 }
@@ -4249,8 +4439,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AExternClasskind___n_kwextern].val; /* _n_kwextern on <self:AExternClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwextern", "src/parser/parser_prod.nit", 1066);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwextern");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1066);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwextern>*/;
 if (var1){
@@ -4271,13 +4462,15 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1069);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1069);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AExternClasskind___n_kwextern].val = var_new_child; /* _n_kwextern on <self:AExternClasskind> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1072);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1072);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -4306,8 +4499,9 @@ var9 = 0;
 var9 = var_new_child->type->type_table[cltype10] == idtype11;
 }
 if (!var9) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1079);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1079);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AExternClasskind___n_kwclass].val = var_new_child; /* _n_kwclass on <self:AExternClasskind> */
 } else {
@@ -4372,8 +4566,9 @@ val* var4 /* : nullable TKwclass */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AExternClasskind___n_kwextern].val; /* _n_kwextern on <self:AExternClasskind> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwextern", "src/parser/parser_prod.nit", 1104);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwextern");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1104);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 var1 = self->attrs[COLOR_parser_nodes__AExternClasskind___n_kwclass].val; /* _n_kwclass on <self:AExternClasskind> */
@@ -4386,8 +4581,9 @@ var3 = 1; /* arg is null and recv is not */
 if (var3){
 var4 = self->attrs[COLOR_parser_nodes__AExternClasskind___n_kwclass].val; /* _n_kwclass on <self:AExternClasskind> */
 if (var4 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1106);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1106);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var4) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -4422,13 +4618,15 @@ var_n_type = p1;
 var_n_annotations = p2;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__AFormaldef__empty_init]))(self) /* empty_init on <self:AFormaldef>*/;
 if (var_n_id == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1120);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1120);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AFormaldef___n_id].val = var_n_id; /* _n_id on <self:AFormaldef> */
 if (var_n_id == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1121);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1121);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_id->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_id, self) /* parent= on <var_n_id:nullable TClassid>*/;
 }
@@ -4492,8 +4690,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__AFormaldef___n_id].val; /* _n_id on <self:AFormaldef> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_id", "src/parser/parser_prod.nit", 1134);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_id");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1134);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TClassid>*/;
 if (var1){
@@ -4514,13 +4713,15 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1137);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1137);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AFormaldef___n_id].val = var_new_child; /* _n_id on <self:AFormaldef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1140);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1140);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -4549,8 +4750,9 @@ var9 = 0;
 var9 = var_new_child->type->type_table[cltype10] == idtype11;
 }
 if (!var9) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1147);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1147);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AFormaldef___n_type].val = var_new_child; /* _n_type on <self:AFormaldef> */
 } else {
@@ -4584,8 +4786,9 @@ var17 = 0;
 var17 = var_new_child->type->type_table[cltype18] == idtype19;
 }
 if (!var17) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1157);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1157);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:AFormaldef> */
 } else {
@@ -4678,8 +4881,9 @@ val* var8 /* : nullable AAnnotations */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__AFormaldef___n_id].val; /* _n_id on <self:AFormaldef> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_id", "src/parser/parser_prod.nit", 1189);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_id");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1189);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 var1 = self->attrs[COLOR_parser_nodes__AFormaldef___n_type].val; /* _n_type on <self:AFormaldef> */
@@ -4692,8 +4896,9 @@ var3 = 1; /* arg is null and recv is not */
 if (var3){
 var4 = self->attrs[COLOR_parser_nodes__AFormaldef___n_type].val; /* _n_type on <self:AFormaldef> */
 if (var4 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1191);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1191);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var4) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -4708,8 +4913,9 @@ var7 = 1; /* arg is null and recv is not */
 if (var7){
 var8 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AFormaldef> */
 if (var8 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1194);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1194);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var8) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -4742,24 +4948,28 @@ var_n_type = p1;
 var_n_annotations = p2;
 ((void (*)(val*))(self->class->vft[COLOR_parser_prod__ASuperclass__empty_init]))(self) /* empty_init on <self:ASuperclass>*/;
 if (var_n_kwsuper == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1208);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1208);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ASuperclass___n_kwsuper].val = var_n_kwsuper; /* _n_kwsuper on <self:ASuperclass> */
 if (var_n_kwsuper == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1209);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1209);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwsuper->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwsuper, self) /* parent= on <var_n_kwsuper:nullable TKwsuper>*/;
 }
 if (var_n_type == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1210);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1210);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ASuperclass___n_type].val = var_n_type; /* _n_type on <self:ASuperclass> */
 if (var_n_type == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1211);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1211);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_type->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_type, self) /* parent= on <var_n_type:nullable AType>*/;
 }
@@ -4811,8 +5021,9 @@ var_old_child = p0;
 var_new_child = p1;
 var = self->attrs[COLOR_parser_nodes__ASuperclass___n_kwsuper].val; /* _n_kwsuper on <self:ASuperclass> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwsuper", "src/parser/parser_prod.nit", 1220);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwsuper");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1220);
+show_backtrace(1);
 }
 var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:TKwsuper>*/;
 if (var1){
@@ -4833,21 +5044,24 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1223);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1223);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ASuperclass___n_kwsuper].val = var_new_child; /* _n_kwsuper on <self:ASuperclass> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1226);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1226);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var5 = self->attrs[COLOR_parser_nodes__ASuperclass___n_type].val; /* _n_type on <self:ASuperclass> */
 if (var5 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_type", "src/parser/parser_prod.nit", 1230);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_type");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1230);
+show_backtrace(1);
 }
 var6 = ((short int (*)(val*, val*))(var5->class->vft[COLOR_kernel__Object___61d_61d]))(var5, var_old_child) /* == on <var5:AType>*/;
 if (var6){
@@ -4868,13 +5082,15 @@ var9 = 0;
 var9 = var_new_child->type->type_table[cltype10] == idtype11;
 }
 if (!var9) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1233);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1233);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ASuperclass___n_type].val = var_new_child; /* _n_type on <self:ASuperclass> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1236);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1236);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -4903,8 +5119,9 @@ var16 = 0;
 var16 = var_new_child->type->type_table[cltype17] == idtype18;
 }
 if (!var16) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1243);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1243);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:ASuperclass> */
 } else {
@@ -4983,14 +5200,16 @@ val* var5 /* : nullable AAnnotations */;
 var_v = p0;
 var = self->attrs[COLOR_parser_nodes__ASuperclass___n_kwsuper].val; /* _n_kwsuper on <self:ASuperclass> */
 if (var == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwsuper", "src/parser/parser_prod.nit", 1273);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwsuper");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1273);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var) /* enter_visit on <var_v:Visitor>*/;
 var1 = self->attrs[COLOR_parser_nodes__ASuperclass___n_type].val; /* _n_type on <self:ASuperclass> */
 if (var1 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_type", "src/parser/parser_prod.nit", 1274);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_type");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1274);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var1) /* enter_visit on <var_v:Visitor>*/;
 var2 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:ASuperclass> */
@@ -5003,8 +5222,9 @@ var4 = 1; /* arg is null and recv is not */
 if (var4){
 var5 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:ASuperclass> */
 if (var5 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1276);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1276);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var5) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -5113,24 +5333,28 @@ if (var7){
 } else {
 }
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1314);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1314);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_visibility].val = var_n_visibility; /* _n_visibility on <self:AAttrPropdef> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1315);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1315);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_kwvar == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1316);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1316);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_kwvar].val = var_n_kwvar; /* _n_kwvar on <self:AAttrPropdef> */
 if (var_n_kwvar == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1317);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1317);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwvar->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwvar, self) /* parent= on <var_n_kwvar:nullable TKwvar>*/;
 }
@@ -5312,8 +5536,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1345);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1345);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var_new_child; /* _n_doc on <self:AAttrPropdef> */
 } else {
@@ -5347,8 +5572,9 @@ var10 = 0;
 var10 = var_new_child->type->type_table[cltype11] == idtype12;
 }
 if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1355);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1355);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_readable].val = var_new_child; /* _n_readable on <self:AAttrPropdef> */
 } else {
@@ -5382,8 +5608,9 @@ var18 = 0;
 var18 = var_new_child->type->type_table[cltype19] == idtype20;
 }
 if (!var18) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1365);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1365);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_writable].val = var_new_child; /* _n_writable on <self:AAttrPropdef> */
 } else {
@@ -5417,8 +5644,9 @@ var26 = 0;
 var26 = var_new_child->type->type_table[cltype27] == idtype28;
 }
 if (!var26) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1375);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1375);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_kwredef].val = var_new_child; /* _n_kwredef on <self:AAttrPropdef> */
 } else {
@@ -5430,8 +5658,9 @@ goto RET_LABEL;
 }
 var30 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_visibility].val; /* _n_visibility on <self:AAttrPropdef> */
 if (var30 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_visibility", "src/parser/parser_prod.nit", 1382);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_visibility");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1382);
+show_backtrace(1);
 }
 var31 = ((short int (*)(val*, val*))(var30->class->vft[COLOR_kernel__Object___61d_61d]))(var30, var_old_child) /* == on <var30:AVisibility>*/;
 if (var31){
@@ -5452,21 +5681,24 @@ var34 = 0;
 var34 = var_new_child->type->type_table[cltype35] == idtype36;
 }
 if (!var34) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1385);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1385);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_visibility].val = var_new_child; /* _n_visibility on <self:AAttrPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1388);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1388);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var37 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_kwvar].val; /* _n_kwvar on <self:AAttrPropdef> */
 if (var37 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwvar", "src/parser/parser_prod.nit", 1392);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwvar");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1392);
+show_backtrace(1);
 }
 var38 = ((short int (*)(val*, val*))(var37->class->vft[COLOR_kernel__Object___61d_61d]))(var37, var_old_child) /* == on <var37:TKwvar>*/;
 if (var38){
@@ -5487,13 +5719,15 @@ var41 = 0;
 var41 = var_new_child->type->type_table[cltype42] == idtype43;
 }
 if (!var41) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1395);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1395);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_kwvar].val = var_new_child; /* _n_kwvar on <self:AAttrPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1398);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1398);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -5522,8 +5756,9 @@ var48 = 0;
 var48 = var_new_child->type->type_table[cltype49] == idtype50;
 }
 if (!var48) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1405);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1405);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_id].val = var_new_child; /* _n_id on <self:AAttrPropdef> */
 } else {
@@ -5557,8 +5792,9 @@ var56 = 0;
 var56 = var_new_child->type->type_table[cltype57] == idtype58;
 }
 if (!var56) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1415);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1415);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_id2].val = var_new_child; /* _n_id2 on <self:AAttrPropdef> */
 } else {
@@ -5592,8 +5828,9 @@ var64 = 0;
 var64 = var_new_child->type->type_table[cltype65] == idtype66;
 }
 if (!var64) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1425);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1425);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_type].val = var_new_child; /* _n_type on <self:AAttrPropdef> */
 } else {
@@ -5627,8 +5864,9 @@ var72 = 0;
 var72 = var_new_child->type->type_table[cltype73] == idtype74;
 }
 if (!var72) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1435);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1435);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:AAttrPropdef> */
 } else {
@@ -5662,8 +5900,9 @@ var80 = 0;
 var80 = var_new_child->type->type_table[cltype81] == idtype82;
 }
 if (!var80) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1445);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1445);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AAttrPropdef___n_expr].val = var_new_child; /* _n_expr on <self:AAttrPropdef> */
 } else {
@@ -5974,8 +6213,9 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__APropdef___n_doc].val; /* _n_doc on <self:AAttrPropdef> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1532);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1532);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -5990,8 +6230,9 @@ var6 = 1; /* arg is null and recv is not */
 if (var6){
 var7 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_readable].val; /* _n_readable on <self:AAttrPropdef> */
 if (var7 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1535);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1535);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var7) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6006,8 +6247,9 @@ var10 = 1; /* arg is null and recv is not */
 if (var10){
 var11 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_writable].val; /* _n_writable on <self:AAttrPropdef> */
 if (var11 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1538);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1538);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var11) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6022,22 +6264,25 @@ var14 = 1; /* arg is null and recv is not */
 if (var14){
 var15 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_kwredef].val; /* _n_kwredef on <self:AAttrPropdef> */
 if (var15 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1541);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1541);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var15) /* enter_visit on <var_v:Visitor>*/;
 } else {
 }
 var16 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_visibility].val; /* _n_visibility on <self:AAttrPropdef> */
 if (var16 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_visibility", "src/parser/parser_prod.nit", 1543);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_visibility");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1543);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var16) /* enter_visit on <var_v:Visitor>*/;
 var17 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_kwvar].val; /* _n_kwvar on <self:AAttrPropdef> */
 if (var17 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwvar", "src/parser/parser_prod.nit", 1544);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwvar");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1544);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var17) /* enter_visit on <var_v:Visitor>*/;
 var18 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_id].val; /* _n_id on <self:AAttrPropdef> */
@@ -6050,8 +6295,9 @@ var20 = 1; /* arg is null and recv is not */
 if (var20){
 var21 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_id].val; /* _n_id on <self:AAttrPropdef> */
 if (var21 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1546);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1546);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var21) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6066,8 +6312,9 @@ var24 = 1; /* arg is null and recv is not */
 if (var24){
 var25 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_id2].val; /* _n_id2 on <self:AAttrPropdef> */
 if (var25 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1549);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1549);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var25) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6082,8 +6329,9 @@ var28 = 1; /* arg is null and recv is not */
 if (var28){
 var29 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_type].val; /* _n_type on <self:AAttrPropdef> */
 if (var29 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1552);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1552);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var29) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6098,8 +6346,9 @@ var32 = 1; /* arg is null and recv is not */
 if (var32){
 var33 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AAttrPropdef> */
 if (var33 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1555);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1555);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var33) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6114,8 +6363,9 @@ var36 = 1; /* arg is null and recv is not */
 if (var36){
 var37 = self->attrs[COLOR_parser_nodes__AAttrPropdef___n_expr].val; /* _n_expr on <self:AAttrPropdef> */
 if (var37 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1558);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1558);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var37) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6176,35 +6426,41 @@ if (var3){
 } else {
 }
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1582);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1582);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_n_visibility; /* _n_visibility on <self:AMethPropdef> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1583);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1583);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1584);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1584);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_n_methid; /* _n_methid on <self:AMethPropdef> */
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1585);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1585);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_methid->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_methid, self) /* parent= on <var_n_methid:nullable AMethid>*/;
 }
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1586);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1586);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_n_signature; /* _n_signature on <self:AMethPropdef> */
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1587);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1587);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_signature->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_signature, self) /* parent= on <var_n_signature:nullable ASignature>*/;
 }
@@ -6282,8 +6538,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1595);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1595);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var_new_child; /* _n_doc on <self:AMethPropdef> */
 } else {
@@ -6317,8 +6574,9 @@ var10 = 0;
 var10 = var_new_child->type->type_table[cltype11] == idtype12;
 }
 if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1605);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1605);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val = var_new_child; /* _n_kwredef on <self:AMethPropdef> */
 } else {
@@ -6352,13 +6610,15 @@ var18 = 0;
 var18 = var_new_child->type->type_table[cltype19] == idtype20;
 }
 if (!var18) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1615);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1615);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_new_child; /* _n_visibility on <self:AMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1618);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1618);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -6387,13 +6647,15 @@ var25 = 0;
 var25 = var_new_child->type->type_table[cltype26] == idtype27;
 }
 if (!var25) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1625);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1625);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_new_child; /* _n_methid on <self:AMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1628);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1628);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -6422,13 +6684,15 @@ var32 = 0;
 var32 = var_new_child->type->type_table[cltype33] == idtype34;
 }
 if (!var32) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1635);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1635);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_new_child; /* _n_signature on <self:AMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1638);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1638);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -6494,8 +6758,9 @@ val* var_node /* var node: nullable AVisibility */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_node; /* _n_visibility on <self:AMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1661);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1661);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AVisibility>*/;
 }
@@ -6512,8 +6777,9 @@ val* var_node /* var node: nullable AMethid */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_node; /* _n_methid on <self:AMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1666);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1666);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AMethid>*/;
 }
@@ -6530,8 +6796,9 @@ val* var_node /* var node: nullable ASignature */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_node; /* _n_signature on <self:AMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1671);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1671);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable ASignature>*/;
 }
@@ -6567,8 +6834,9 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__APropdef___n_doc].val; /* _n_doc on <self:AMethPropdef> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1678);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1678);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6583,8 +6851,9 @@ var6 = 1; /* arg is null and recv is not */
 if (var6){
 var7 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val; /* _n_kwredef on <self:AMethPropdef> */
 if (var7 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1681);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1681);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var7) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -6657,46 +6926,54 @@ if (var3){
 } else {
 }
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1710);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1710);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_n_visibility; /* _n_visibility on <self:ADeferredMethPropdef> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1711);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1711);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_kwmeth == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1712);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1712);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ADeferredMethPropdef___n_kwmeth].val = var_n_kwmeth; /* _n_kwmeth on <self:ADeferredMethPropdef> */
 if (var_n_kwmeth == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1713);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1713);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwmeth->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwmeth, self) /* parent= on <var_n_kwmeth:nullable TKwmeth>*/;
 }
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1714);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1714);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_n_methid; /* _n_methid on <self:ADeferredMethPropdef> */
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1715);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1715);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_methid->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_methid, self) /* parent= on <var_n_methid:nullable AMethid>*/;
 }
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1716);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1716);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_n_signature; /* _n_signature on <self:ADeferredMethPropdef> */
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1717);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1717);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_signature->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_signature, self) /* parent= on <var_n_signature:nullable ASignature>*/;
 }
@@ -6800,8 +7077,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1729);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1729);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var_new_child; /* _n_doc on <self:ADeferredMethPropdef> */
 } else {
@@ -6835,8 +7113,9 @@ var10 = 0;
 var10 = var_new_child->type->type_table[cltype11] == idtype12;
 }
 if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1739);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1739);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val = var_new_child; /* _n_kwredef on <self:ADeferredMethPropdef> */
 } else {
@@ -6870,21 +7149,24 @@ var18 = 0;
 var18 = var_new_child->type->type_table[cltype19] == idtype20;
 }
 if (!var18) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1749);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1749);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_new_child; /* _n_visibility on <self:ADeferredMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1752);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1752);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var21 = self->attrs[COLOR_parser_nodes__ADeferredMethPropdef___n_kwmeth].val; /* _n_kwmeth on <self:ADeferredMethPropdef> */
 if (var21 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwmeth", "src/parser/parser_prod.nit", 1756);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwmeth");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1756);
+show_backtrace(1);
 }
 var22 = ((short int (*)(val*, val*))(var21->class->vft[COLOR_kernel__Object___61d_61d]))(var21, var_old_child) /* == on <var21:TKwmeth>*/;
 if (var22){
@@ -6905,13 +7187,15 @@ var25 = 0;
 var25 = var_new_child->type->type_table[cltype26] == idtype27;
 }
 if (!var25) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1759);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1759);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__ADeferredMethPropdef___n_kwmeth].val = var_new_child; /* _n_kwmeth on <self:ADeferredMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1762);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1762);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -6940,13 +7224,15 @@ var32 = 0;
 var32 = var_new_child->type->type_table[cltype33] == idtype34;
 }
 if (!var32) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1769);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1769);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_new_child; /* _n_methid on <self:ADeferredMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1772);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1772);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -6975,13 +7261,15 @@ var39 = 0;
 var39 = var_new_child->type->type_table[cltype40] == idtype41;
 }
 if (!var39) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1779);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1779);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_new_child; /* _n_signature on <self:ADeferredMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1782);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1782);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -7010,8 +7298,9 @@ var46 = 0;
 var46 = var_new_child->type->type_table[cltype47] == idtype48;
 }
 if (!var46) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1789);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1789);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:ADeferredMethPropdef> */
 } else {
@@ -7082,8 +7371,9 @@ val* var_node /* var node: nullable AVisibility */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_node; /* _n_visibility on <self:ADeferredMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1815);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1815);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AVisibility>*/;
 }
@@ -7113,8 +7403,9 @@ val* var_node /* var node: nullable AMethid */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_node; /* _n_methid on <self:ADeferredMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1825);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1825);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AMethid>*/;
 }
@@ -7131,8 +7422,9 @@ val* var_node /* var node: nullable ASignature */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_node; /* _n_signature on <self:ADeferredMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1830);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1830);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable ASignature>*/;
 }
@@ -7197,8 +7489,9 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__APropdef___n_doc].val; /* _n_doc on <self:ADeferredMethPropdef> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1844);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1844);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -7213,8 +7506,9 @@ var6 = 1; /* arg is null and recv is not */
 if (var6){
 var7 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val; /* _n_kwredef on <self:ADeferredMethPropdef> */
 if (var7 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1847);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1847);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var7) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -7223,8 +7517,9 @@ var8 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val; /* _n_v
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var8) /* enter_visit on <var_v:Visitor>*/;
 var9 = self->attrs[COLOR_parser_nodes__ADeferredMethPropdef___n_kwmeth].val; /* _n_kwmeth on <self:ADeferredMethPropdef> */
 if (var9 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwmeth", "src/parser/parser_prod.nit", 1850);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwmeth");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1850);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var9) /* enter_visit on <var_v:Visitor>*/;
 var10 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val; /* _n_methid on <self:ADeferredMethPropdef> */
@@ -7241,8 +7536,9 @@ var14 = 1; /* arg is null and recv is not */
 if (var14){
 var15 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:ADeferredMethPropdef> */
 if (var15 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1854);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1854);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var15) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -7305,46 +7601,54 @@ if (var3){
 } else {
 }
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1879);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1879);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_n_visibility; /* _n_visibility on <self:AInternMethPropdef> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1880);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1880);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_kwmeth == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1881);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1881);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AInternMethPropdef___n_kwmeth].val = var_n_kwmeth; /* _n_kwmeth on <self:AInternMethPropdef> */
 if (var_n_kwmeth == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1882);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1882);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwmeth->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwmeth, self) /* parent= on <var_n_kwmeth:nullable TKwmeth>*/;
 }
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1883);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1883);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_n_methid; /* _n_methid on <self:AInternMethPropdef> */
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1884);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1884);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_methid->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_methid, self) /* parent= on <var_n_methid:nullable AMethid>*/;
 }
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1885);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1885);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_n_signature; /* _n_signature on <self:AInternMethPropdef> */
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1886);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1886);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_signature->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_signature, self) /* parent= on <var_n_signature:nullable ASignature>*/;
 }
@@ -7429,8 +7733,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1894);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1894);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var_new_child; /* _n_doc on <self:AInternMethPropdef> */
 } else {
@@ -7464,8 +7769,9 @@ var10 = 0;
 var10 = var_new_child->type->type_table[cltype11] == idtype12;
 }
 if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1904);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1904);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val = var_new_child; /* _n_kwredef on <self:AInternMethPropdef> */
 } else {
@@ -7499,21 +7805,24 @@ var18 = 0;
 var18 = var_new_child->type->type_table[cltype19] == idtype20;
 }
 if (!var18) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1914);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1914);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_new_child; /* _n_visibility on <self:AInternMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1917);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1917);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var21 = self->attrs[COLOR_parser_nodes__AInternMethPropdef___n_kwmeth].val; /* _n_kwmeth on <self:AInternMethPropdef> */
 if (var21 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwmeth", "src/parser/parser_prod.nit", 1921);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwmeth");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1921);
+show_backtrace(1);
 }
 var22 = ((short int (*)(val*, val*))(var21->class->vft[COLOR_kernel__Object___61d_61d]))(var21, var_old_child) /* == on <var21:TKwmeth>*/;
 if (var22){
@@ -7534,13 +7843,15 @@ var25 = 0;
 var25 = var_new_child->type->type_table[cltype26] == idtype27;
 }
 if (!var25) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1924);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1924);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AInternMethPropdef___n_kwmeth].val = var_new_child; /* _n_kwmeth on <self:AInternMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1927);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1927);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -7569,13 +7880,15 @@ var32 = 0;
 var32 = var_new_child->type->type_table[cltype33] == idtype34;
 }
 if (!var32) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1934);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1934);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_new_child; /* _n_methid on <self:AInternMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1937);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1937);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -7604,13 +7917,15 @@ var39 = 0;
 var39 = var_new_child->type->type_table[cltype40] == idtype41;
 }
 if (!var39) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 1944);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1944);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_new_child; /* _n_signature on <self:AInternMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 1947);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1947);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -7676,8 +7991,9 @@ val* var_node /* var node: nullable AVisibility */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_node; /* _n_visibility on <self:AInternMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1970);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1970);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AVisibility>*/;
 }
@@ -7707,8 +8023,9 @@ val* var_node /* var node: nullable AMethid */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_node; /* _n_methid on <self:AInternMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1980);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1980);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AMethid>*/;
 }
@@ -7725,8 +8042,9 @@ val* var_node /* var node: nullable ASignature */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_node; /* _n_signature on <self:AInternMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 1985);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1985);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable ASignature>*/;
 }
@@ -7763,8 +8081,9 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__APropdef___n_doc].val; /* _n_doc on <self:AInternMethPropdef> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1992);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1992);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -7779,8 +8098,9 @@ var6 = 1; /* arg is null and recv is not */
 if (var6){
 var7 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val; /* _n_kwredef on <self:AInternMethPropdef> */
 if (var7 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 1995);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1995);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var7) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -7789,8 +8109,9 @@ var8 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val; /* _n_v
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var8) /* enter_visit on <var_v:Visitor>*/;
 var9 = self->attrs[COLOR_parser_nodes__AInternMethPropdef___n_kwmeth].val; /* _n_kwmeth on <self:AInternMethPropdef> */
 if (var9 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwmeth", "src/parser/parser_prod.nit", 1998);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwmeth");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 1998);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var9) /* enter_visit on <var_v:Visitor>*/;
 var10 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val; /* _n_methid on <self:AInternMethPropdef> */
@@ -7867,46 +8188,54 @@ if (var3){
 } else {
 }
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2027);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2027);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_n_visibility; /* _n_visibility on <self:AExternMethPropdef> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2028);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2028);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_kwmeth == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2029);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2029);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AExternMethPropdef___n_kwmeth].val = var_n_kwmeth; /* _n_kwmeth on <self:AExternMethPropdef> */
 if (var_n_kwmeth == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2030);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2030);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwmeth->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwmeth, self) /* parent= on <var_n_kwmeth:nullable TKwmeth>*/;
 }
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2031);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2031);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_n_methid; /* _n_methid on <self:AExternMethPropdef> */
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2032);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2032);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_methid->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_methid, self) /* parent= on <var_n_methid:nullable AMethid>*/;
 }
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2033);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2033);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_n_signature; /* _n_signature on <self:AExternMethPropdef> */
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2034);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2034);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_signature->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_signature, self) /* parent= on <var_n_signature:nullable ASignature>*/;
 }
@@ -8048,8 +8377,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2054);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2054);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var_new_child; /* _n_doc on <self:AExternMethPropdef> */
 } else {
@@ -8083,8 +8413,9 @@ var10 = 0;
 var10 = var_new_child->type->type_table[cltype11] == idtype12;
 }
 if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2064);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2064);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val = var_new_child; /* _n_kwredef on <self:AExternMethPropdef> */
 } else {
@@ -8118,21 +8449,24 @@ var18 = 0;
 var18 = var_new_child->type->type_table[cltype19] == idtype20;
 }
 if (!var18) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2074);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2074);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_new_child; /* _n_visibility on <self:AExternMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2077);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2077);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
 }
 var21 = self->attrs[COLOR_parser_nodes__AExternMethPropdef___n_kwmeth].val; /* _n_kwmeth on <self:AExternMethPropdef> */
 if (var21 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwmeth", "src/parser/parser_prod.nit", 2081);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwmeth");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2081);
+show_backtrace(1);
 }
 var22 = ((short int (*)(val*, val*))(var21->class->vft[COLOR_kernel__Object___61d_61d]))(var21, var_old_child) /* == on <var21:TKwmeth>*/;
 if (var22){
@@ -8153,13 +8487,15 @@ var25 = 0;
 var25 = var_new_child->type->type_table[cltype26] == idtype27;
 }
 if (!var25) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2084);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2084);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AExternMethPropdef___n_kwmeth].val = var_new_child; /* _n_kwmeth on <self:AExternMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2087);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2087);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -8188,13 +8524,15 @@ var32 = 0;
 var32 = var_new_child->type->type_table[cltype33] == idtype34;
 }
 if (!var32) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2094);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2094);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_new_child; /* _n_methid on <self:AExternMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2097);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2097);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -8223,13 +8561,15 @@ var39 = 0;
 var39 = var_new_child->type->type_table[cltype40] == idtype41;
 }
 if (!var39) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2104);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2104);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_new_child; /* _n_signature on <self:AExternMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2107);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2107);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -8258,8 +8598,9 @@ var46 = 0;
 var46 = var_new_child->type->type_table[cltype47] == idtype48;
 }
 if (!var46) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2114);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2114);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AExternPropdef___n_extern].val = var_new_child; /* _n_extern on <self:AExternMethPropdef> */
 } else {
@@ -8293,8 +8634,9 @@ var54 = 0;
 var54 = var_new_child->type->type_table[cltype55] == idtype56;
 }
 if (!var54) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2124);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2124);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AExternPropdef___n_extern_calls].val = var_new_child; /* _n_extern_calls on <self:AExternMethPropdef> */
 } else {
@@ -8328,8 +8670,9 @@ var62 = 0;
 var62 = var_new_child->type->type_table[cltype63] == idtype64;
 }
 if (!var62) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2134);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2134);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AExternPropdef___n_extern_code_block].val = var_new_child; /* _n_extern_code_block on <self:AExternMethPropdef> */
 } else {
@@ -8400,8 +8743,9 @@ val* var_node /* var node: nullable AVisibility */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_node; /* _n_visibility on <self:AExternMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2160);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2160);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AVisibility>*/;
 }
@@ -8431,8 +8775,9 @@ val* var_node /* var node: nullable AMethid */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_node; /* _n_methid on <self:AExternMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2170);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2170);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AMethid>*/;
 }
@@ -8449,8 +8794,9 @@ val* var_node /* var node: nullable ASignature */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_node; /* _n_signature on <self:AExternMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2175);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2175);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable ASignature>*/;
 }
@@ -8571,8 +8917,9 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__APropdef___n_doc].val; /* _n_doc on <self:AExternMethPropdef> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2203);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2203);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -8587,8 +8934,9 @@ var6 = 1; /* arg is null and recv is not */
 if (var6){
 var7 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val; /* _n_kwredef on <self:AExternMethPropdef> */
 if (var7 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2206);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2206);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var7) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -8597,8 +8945,9 @@ var8 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val; /* _n_v
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var8) /* enter_visit on <var_v:Visitor>*/;
 var9 = self->attrs[COLOR_parser_nodes__AExternMethPropdef___n_kwmeth].val; /* _n_kwmeth on <self:AExternMethPropdef> */
 if (var9 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwmeth", "src/parser/parser_prod.nit", 2209);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Uninitialized attribute _n_kwmeth");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2209);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var9) /* enter_visit on <var_v:Visitor>*/;
 var10 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val; /* _n_methid on <self:AExternMethPropdef> */
@@ -8615,8 +8964,9 @@ var14 = 1; /* arg is null and recv is not */
 if (var14){
 var15 = self->attrs[COLOR_parser_nodes__AExternPropdef___n_extern].val; /* _n_extern on <self:AExternMethPropdef> */
 if (var15 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2213);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2213);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var15) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -8631,8 +8981,9 @@ var18 = 1; /* arg is null and recv is not */
 if (var18){
 var19 = self->attrs[COLOR_parser_nodes__AExternPropdef___n_extern_calls].val; /* _n_extern_calls on <self:AExternMethPropdef> */
 if (var19 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2216);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2216);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var19) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -8647,8 +8998,9 @@ var22 = 1; /* arg is null and recv is not */
 if (var22){
 var23 = self->attrs[COLOR_parser_nodes__AExternPropdef___n_extern_code_block].val; /* _n_extern_code_block on <self:AExternMethPropdef> */
 if (var23 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2219);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2219);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var23) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -8719,46 +9071,54 @@ if (var3){
 } else {
 }
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2246);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2246);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_n_visibility; /* _n_visibility on <self:AConcreteMethPropdef> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2247);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2247);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_kwmeth == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2248);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2248);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AConcreteMethPropdef___n_kwmeth].val = var_n_kwmeth; /* _n_kwmeth on <self:AConcreteMethPropdef> */
 if (var_n_kwmeth == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2249);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2249);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwmeth->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwmeth, self) /* parent= on <var_n_kwmeth:nullable TKwmeth>*/;
 }
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2250);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2250);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_n_methid; /* _n_methid on <self:AConcreteMethPropdef> */
 if (var_n_methid == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2251);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2251);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_methid->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_methid, self) /* parent= on <var_n_methid:nullable AMethid>*/;
 }
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2252);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2252);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_n_signature; /* _n_signature on <self:AConcreteMethPropdef> */
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2253);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2253);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_signature->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_signature, self) /* parent= on <var_n_signature:nullable ASignature>*/;
 }
@@ -8881,8 +9241,9 @@ var4 = 0;
 var4 = var_new_child->type->type_table[cltype] == idtype;
 }
 if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2269);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2269);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var_new_child; /* _n_doc on <self:AConcreteMethPropdef> */
 } else {
@@ -8916,8 +9277,9 @@ var10 = 0;
 var10 = var_new_child->type->type_table[cltype11] == idtype12;
 }
 if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2279);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2279);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val = var_new_child; /* _n_kwredef on <self:AConcreteMethPropdef> */
 } else {
@@ -8951,13 +9313,15 @@ var18 = 0;
 var18 = var_new_child->type->type_table[cltype19] == idtype20;
 }
 if (!var18) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2289);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2289);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_new_child; /* _n_visibility on <self:AConcreteMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2292);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2292);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -8986,13 +9350,15 @@ var25 = 0;
 var25 = var_new_child->type->type_table[cltype26] == idtype27;
 }
 if (!var25) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2299);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2299);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AConcreteMethPropdef___n_kwmeth].val = var_new_child; /* _n_kwmeth on <self:AConcreteMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2302);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2302);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -9021,13 +9387,15 @@ var32 = 0;
 var32 = var_new_child->type->type_table[cltype33] == idtype34;
 }
 if (!var32) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2309);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2309);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_new_child; /* _n_methid on <self:AConcreteMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2312);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2312);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -9056,13 +9424,15 @@ var39 = 0;
 var39 = var_new_child->type->type_table[cltype40] == idtype41;
 }
 if (!var39) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2319);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2319);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_new_child; /* _n_signature on <self:AConcreteMethPropdef> */
 } else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2322);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Aborted");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2322);
+show_backtrace(1);
 }
 goto RET_LABEL;
 } else {
@@ -9091,8 +9461,9 @@ var46 = 0;
 var46 = var_new_child->type->type_table[cltype47] == idtype48;
 }
 if (!var46) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2329);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2329);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:AConcreteMethPropdef> */
 } else {
@@ -9126,8 +9497,9 @@ var54 = 0;
 var54 = var_new_child->type->type_table[cltype55] == idtype56;
 }
 if (!var54) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2339);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Assert failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2339);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AConcreteMethPropdef___n_block].val = var_new_child; /* _n_block on <self:AConcreteMethPropdef> */
 } else {
@@ -9198,8 +9570,9 @@ val* var_node /* var node: nullable AVisibility */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_node; /* _n_visibility on <self:AConcreteMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2365);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2365);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AVisibility>*/;
 }
@@ -9216,8 +9589,9 @@ val* var_node /* var node: nullable TKwmeth */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AConcreteMethPropdef___n_kwmeth].val = var_node; /* _n_kwmeth on <self:AConcreteMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2370);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2370);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable TKwmeth>*/;
 }
@@ -9234,8 +9608,9 @@ val* var_node /* var node: nullable AMethid */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_node; /* _n_methid on <self:AConcreteMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2375);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2375);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AMethid>*/;
 }
@@ -9252,8 +9627,9 @@ val* var_node /* var node: nullable ASignature */;
 var_node = p0;
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_node; /* _n_signature on <self:AConcreteMethPropdef> */
 if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2380);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2380);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable ASignature>*/;
 }
@@ -9346,8 +9722,9 @@ var2 = 1; /* arg is null and recv is not */
 if (var2){
 var3 = self->attrs[COLOR_parser_nodes__APropdef___n_doc].val; /* _n_doc on <self:AConcreteMethPropdef> */
 if (var3 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2401);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2401);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var3) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -9362,8 +9739,9 @@ var6 = 1; /* arg is null and recv is not */
 if (var6){
 var7 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val; /* _n_kwredef on <self:AConcreteMethPropdef> */
 if (var7 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2404);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2404);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var7) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -9386,8 +9764,9 @@ var14 = 1; /* arg is null and recv is not */
 if (var14){
 var15 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AConcreteMethPropdef> */
 if (var15 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2411);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2411);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var15) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -9402,8 +9781,9 @@ var18 = 1; /* arg is null and recv is not */
 if (var18){
 var19 = self->attrs[COLOR_parser_nodes__AConcreteMethPropdef___n_block].val; /* _n_block on <self:AConcreteMethPropdef> */
 if (var19 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2414);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2414);
+show_backtrace(1);
 }
 ((void (*)(val*, val*))(var_v->class->vft[COLOR_parser_nodes__Visitor__enter_visit]))(var_v, var19) /* enter_visit on <var_v:Visitor>*/;
 } else {
@@ -9476,24 +9856,28 @@ if (var3){
 } else {
 }
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2441);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2441);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_n_visibility; /* _n_visibility on <self:AConcreteInitPropdef> */
 if (var_n_visibility == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2442);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2442);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_visibility->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_visibility, self) /* parent= on <var_n_visibility:nullable AVisibility>*/;
 }
 if (var_n_kwinit == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2443);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2443);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AConcreteInitPropdef___n_kwinit].val = var_n_kwinit; /* _n_kwinit on <self:AConcreteInitPropdef> */
 if (var_n_kwinit == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2444);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2444);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_kwinit->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_kwinit, self) /* parent= on <var_n_kwinit:nullable TKwinit>*/;
 }
@@ -9509,13 +9893,15 @@ if (var5){
 } else {
 }
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "src/parser/parser_prod.nit", 2449);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Cast failed");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2449);
+show_backtrace(1);
 }
 self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_n_signature; /* _n_signature on <self:AConcreteInitPropdef> */
 if (var_n_signature == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2450);
-exit(1);
+fprintf(stderr, "Runtime error: %s", "Receiver is null");
+fprintf(stderr, " (%s:%d)\n", "src/parser/parser_prod.nit", 2450);
+show_backtrace(1);
 } else {
 ((void (*)(val*, val*))(var_n_signature->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_n_signature, self) /* parent= on <var_n_signature:nullable ASignature>*/;
 }
@@ -9548,436 +9934,3 @@ void VIRTUAL_parser_prod__AConcreteInitPropdef__init_aconcreteinitpropdef(val* s
 parser_prod__AConcreteInitPropdef__init_aconcreteinitpropdef(self, p0, p1, p2, p3, p4, p5, p6, p7);
 RET_LABEL:;
 }
-/* method parser_prod#AConcreteInitPropdef#replace_child for (self: AConcreteInitPropdef, ANode, nullable ANode) */
-void parser_prod__AConcreteInitPropdef__replace_child(val* self, val* p0, val* p1) {
-val* var_old_child /* var old_child: ANode */;
-val* var_new_child /* var new_child: nullable ANode */;
-val* var /* : nullable ADoc */;
-short int var1 /* : Bool */;
-val* var2 /* : null */;
-short int var3 /* : Bool */;
-short int var4 /* : Bool */;
-int cltype;
-int idtype;
-val* var5 /* : null */;
-val* var6 /* : nullable TKwredef */;
-short int var7 /* : Bool */;
-val* var8 /* : null */;
-short int var9 /* : Bool */;
-short int var10 /* : Bool */;
-int cltype11;
-int idtype12;
-val* var13 /* : null */;
-val* var14 /* : nullable AVisibility */;
-short int var15 /* : Bool */;
-val* var16 /* : null */;
-short int var17 /* : Bool */;
-short int var18 /* : Bool */;
-int cltype19;
-int idtype20;
-val* var21 /* : TKwinit */;
-short int var22 /* : Bool */;
-val* var23 /* : null */;
-short int var24 /* : Bool */;
-short int var25 /* : Bool */;
-int cltype26;
-int idtype27;
-val* var28 /* : nullable AMethid */;
-short int var29 /* : Bool */;
-val* var30 /* : null */;
-short int var31 /* : Bool */;
-short int var32 /* : Bool */;
-int cltype33;
-int idtype34;
-val* var35 /* : null */;
-val* var36 /* : nullable ASignature */;
-short int var37 /* : Bool */;
-val* var38 /* : null */;
-short int var39 /* : Bool */;
-short int var40 /* : Bool */;
-int cltype41;
-int idtype42;
-val* var43 /* : nullable AAnnotations */;
-short int var44 /* : Bool */;
-val* var45 /* : null */;
-short int var46 /* : Bool */;
-short int var47 /* : Bool */;
-int cltype48;
-int idtype49;
-val* var50 /* : null */;
-val* var51 /* : nullable AExpr */;
-short int var52 /* : Bool */;
-val* var53 /* : null */;
-short int var54 /* : Bool */;
-short int var55 /* : Bool */;
-int cltype56;
-int idtype57;
-val* var58 /* : null */;
-var_old_child = p0;
-var_new_child = p1;
-var = self->attrs[COLOR_parser_nodes__APropdef___n_doc].val; /* _n_doc on <self:AConcreteInitPropdef> */
-if (var == NULL) {
-var1 = 0; /* <var_old_child:ANode> cannot be null */
-} else {
-var1 = ((short int (*)(val*, val*))(var->class->vft[COLOR_kernel__Object___61d_61d]))(var, var_old_child) /* == on <var:nullable ADoc>*/;
-}
-if (var1){
-var2 = NULL;
-if (var_new_child == NULL) {
-var3 = 0; /* is null */
-} else {
-var3 = 1; /* arg is null and recv is not */
-}
-if (var3){
-((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ANode)>*/;
-/* <var_new_child:nullable ANode(ANode)> isa ADoc */
-cltype = type_parser_nodes__ADoc.color;
-idtype = type_parser_nodes__ADoc.id;
-if(cltype >= var_new_child->type->table_size) {
-var4 = 0;
-} else {
-var4 = var_new_child->type->type_table[cltype] == idtype;
-}
-if (!var4) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2466);
-exit(1);
-}
-self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var_new_child; /* _n_doc on <self:AConcreteInitPropdef> */
-} else {
-var5 = NULL;
-self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var5; /* _n_doc on <self:AConcreteInitPropdef> */
-}
-goto RET_LABEL;
-} else {
-}
-var6 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val; /* _n_kwredef on <self:AConcreteInitPropdef> */
-if (var6 == NULL) {
-var7 = 0; /* <var_old_child:ANode> cannot be null */
-} else {
-var7 = ((short int (*)(val*, val*))(var6->class->vft[COLOR_kernel__Object___61d_61d]))(var6, var_old_child) /* == on <var6:nullable TKwredef>*/;
-}
-if (var7){
-var8 = NULL;
-if (var_new_child == NULL) {
-var9 = 0; /* is null */
-} else {
-var9 = 1; /* arg is null and recv is not */
-}
-if (var9){
-((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ANode)>*/;
-/* <var_new_child:nullable ANode(ANode)> isa TKwredef */
-cltype11 = type_parser_nodes__TKwredef.color;
-idtype12 = type_parser_nodes__TKwredef.id;
-if(cltype11 >= var_new_child->type->table_size) {
-var10 = 0;
-} else {
-var10 = var_new_child->type->type_table[cltype11] == idtype12;
-}
-if (!var10) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2476);
-exit(1);
-}
-self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val = var_new_child; /* _n_kwredef on <self:AConcreteInitPropdef> */
-} else {
-var13 = NULL;
-self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val = var13; /* _n_kwredef on <self:AConcreteInitPropdef> */
-}
-goto RET_LABEL;
-} else {
-}
-var14 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val; /* _n_visibility on <self:AConcreteInitPropdef> */
-if (var14 == NULL) {
-var15 = 0; /* <var_old_child:ANode> cannot be null */
-} else {
-var15 = ((short int (*)(val*, val*))(var14->class->vft[COLOR_kernel__Object___61d_61d]))(var14, var_old_child) /* == on <var14:nullable AVisibility>*/;
-}
-if (var15){
-var16 = NULL;
-if (var_new_child == NULL) {
-var17 = 0; /* is null */
-} else {
-var17 = 1; /* arg is null and recv is not */
-}
-if (var17){
-((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ANode)>*/;
-/* <var_new_child:nullable ANode(ANode)> isa AVisibility */
-cltype19 = type_parser_nodes__AVisibility.color;
-idtype20 = type_parser_nodes__AVisibility.id;
-if(cltype19 >= var_new_child->type->table_size) {
-var18 = 0;
-} else {
-var18 = var_new_child->type->type_table[cltype19] == idtype20;
-}
-if (!var18) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2486);
-exit(1);
-}
-self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_new_child; /* _n_visibility on <self:AConcreteInitPropdef> */
-} else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2489);
-exit(1);
-}
-goto RET_LABEL;
-} else {
-}
-var21 = self->attrs[COLOR_parser_nodes__AConcreteInitPropdef___n_kwinit].val; /* _n_kwinit on <self:AConcreteInitPropdef> */
-if (var21 == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Uninitialized attribute _n_kwinit", "src/parser/parser_prod.nit", 2493);
-exit(1);
-}
-var22 = ((short int (*)(val*, val*))(var21->class->vft[COLOR_kernel__Object___61d_61d]))(var21, var_old_child) /* == on <var21:TKwinit>*/;
-if (var22){
-var23 = NULL;
-if (var_new_child == NULL) {
-var24 = 0; /* is null */
-} else {
-var24 = 1; /* arg is null and recv is not */
-}
-if (var24){
-((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ANode)>*/;
-/* <var_new_child:nullable ANode(ANode)> isa TKwinit */
-cltype26 = type_parser_nodes__TKwinit.color;
-idtype27 = type_parser_nodes__TKwinit.id;
-if(cltype26 >= var_new_child->type->table_size) {
-var25 = 0;
-} else {
-var25 = var_new_child->type->type_table[cltype26] == idtype27;
-}
-if (!var25) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2496);
-exit(1);
-}
-self->attrs[COLOR_parser_nodes__AConcreteInitPropdef___n_kwinit].val = var_new_child; /* _n_kwinit on <self:AConcreteInitPropdef> */
-} else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2499);
-exit(1);
-}
-goto RET_LABEL;
-} else {
-}
-var28 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val; /* _n_methid on <self:AConcreteInitPropdef> */
-if (var28 == NULL) {
-var29 = 0; /* <var_old_child:ANode> cannot be null */
-} else {
-var29 = ((short int (*)(val*, val*))(var28->class->vft[COLOR_kernel__Object___61d_61d]))(var28, var_old_child) /* == on <var28:nullable AMethid>*/;
-}
-if (var29){
-var30 = NULL;
-if (var_new_child == NULL) {
-var31 = 0; /* is null */
-} else {
-var31 = 1; /* arg is null and recv is not */
-}
-if (var31){
-((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ANode)>*/;
-/* <var_new_child:nullable ANode(ANode)> isa AMethid */
-cltype33 = type_parser_nodes__AMethid.color;
-idtype34 = type_parser_nodes__AMethid.id;
-if(cltype33 >= var_new_child->type->table_size) {
-var32 = 0;
-} else {
-var32 = var_new_child->type->type_table[cltype33] == idtype34;
-}
-if (!var32) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2506);
-exit(1);
-}
-self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var_new_child; /* _n_methid on <self:AConcreteInitPropdef> */
-} else {
-var35 = NULL;
-self->attrs[COLOR_parser_nodes__AMethPropdef___n_methid].val = var35; /* _n_methid on <self:AConcreteInitPropdef> */
-}
-goto RET_LABEL;
-} else {
-}
-var36 = self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val; /* _n_signature on <self:AConcreteInitPropdef> */
-if (var36 == NULL) {
-var37 = 0; /* <var_old_child:ANode> cannot be null */
-} else {
-var37 = ((short int (*)(val*, val*))(var36->class->vft[COLOR_kernel__Object___61d_61d]))(var36, var_old_child) /* == on <var36:nullable ASignature>*/;
-}
-if (var37){
-var38 = NULL;
-if (var_new_child == NULL) {
-var39 = 0; /* is null */
-} else {
-var39 = 1; /* arg is null and recv is not */
-}
-if (var39){
-((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ANode)>*/;
-/* <var_new_child:nullable ANode(ANode)> isa ASignature */
-cltype41 = type_parser_nodes__ASignature.color;
-idtype42 = type_parser_nodes__ASignature.id;
-if(cltype41 >= var_new_child->type->table_size) {
-var40 = 0;
-} else {
-var40 = var_new_child->type->type_table[cltype41] == idtype42;
-}
-if (!var40) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2516);
-exit(1);
-}
-self->attrs[COLOR_parser_nodes__AMethPropdef___n_signature].val = var_new_child; /* _n_signature on <self:AConcreteInitPropdef> */
-} else {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Aborted", "src/parser/parser_prod.nit", 2519);
-exit(1);
-}
-goto RET_LABEL;
-} else {
-}
-var43 = self->attrs[COLOR_parser_nodes__Prod___n_annotations].val; /* _n_annotations on <self:AConcreteInitPropdef> */
-if (var43 == NULL) {
-var44 = 0; /* <var_old_child:ANode> cannot be null */
-} else {
-var44 = ((short int (*)(val*, val*))(var43->class->vft[COLOR_kernel__Object___61d_61d]))(var43, var_old_child) /* == on <var43:nullable AAnnotations>*/;
-}
-if (var44){
-var45 = NULL;
-if (var_new_child == NULL) {
-var46 = 0; /* is null */
-} else {
-var46 = 1; /* arg is null and recv is not */
-}
-if (var46){
-((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ANode)>*/;
-/* <var_new_child:nullable ANode(ANode)> isa AAnnotations */
-cltype48 = type_parser_nodes__AAnnotations.color;
-idtype49 = type_parser_nodes__AAnnotations.id;
-if(cltype48 >= var_new_child->type->table_size) {
-var47 = 0;
-} else {
-var47 = var_new_child->type->type_table[cltype48] == idtype49;
-}
-if (!var47) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2526);
-exit(1);
-}
-self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var_new_child; /* _n_annotations on <self:AConcreteInitPropdef> */
-} else {
-var50 = NULL;
-self->attrs[COLOR_parser_nodes__Prod___n_annotations].val = var50; /* _n_annotations on <self:AConcreteInitPropdef> */
-}
-goto RET_LABEL;
-} else {
-}
-var51 = self->attrs[COLOR_parser_nodes__AConcreteMethPropdef___n_block].val; /* _n_block on <self:AConcreteInitPropdef> */
-if (var51 == NULL) {
-var52 = 0; /* <var_old_child:ANode> cannot be null */
-} else {
-var52 = ((short int (*)(val*, val*))(var51->class->vft[COLOR_kernel__Object___61d_61d]))(var51, var_old_child) /* == on <var51:nullable AExpr>*/;
-}
-if (var52){
-var53 = NULL;
-if (var_new_child == NULL) {
-var54 = 0; /* is null */
-} else {
-var54 = 1; /* arg is null and recv is not */
-}
-if (var54){
-((void (*)(val*, val*))(var_new_child->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_new_child, self) /* parent= on <var_new_child:nullable ANode(ANode)>*/;
-/* <var_new_child:nullable ANode(ANode)> isa AExpr */
-cltype56 = type_parser_nodes__AExpr.color;
-idtype57 = type_parser_nodes__AExpr.id;
-if(cltype56 >= var_new_child->type->table_size) {
-var55 = 0;
-} else {
-var55 = var_new_child->type->type_table[cltype56] == idtype57;
-}
-if (!var55) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Assert failed", "src/parser/parser_prod.nit", 2536);
-exit(1);
-}
-self->attrs[COLOR_parser_nodes__AConcreteMethPropdef___n_block].val = var_new_child; /* _n_block on <self:AConcreteInitPropdef> */
-} else {
-var58 = NULL;
-self->attrs[COLOR_parser_nodes__AConcreteMethPropdef___n_block].val = var58; /* _n_block on <self:AConcreteInitPropdef> */
-}
-goto RET_LABEL;
-} else {
-}
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#replace_child for (self: Object, ANode, nullable ANode) */
-void VIRTUAL_parser_prod__AConcreteInitPropdef__replace_child(val* self, val* p0, val* p1) {
-parser_prod__AConcreteInitPropdef__replace_child(self, p0, p1);
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#n_doc= for (self: AConcreteInitPropdef, nullable ADoc) */
-void parser_prod__AConcreteInitPropdef__n_doc_61d(val* self, val* p0) {
-val* var_node /* var node: nullable ADoc */;
-val* var /* : null */;
-short int var1 /* : Bool */;
-var_node = p0;
-self->attrs[COLOR_parser_nodes__APropdef___n_doc].val = var_node; /* _n_doc on <self:AConcreteInitPropdef> */
-var = NULL;
-if (var_node == NULL) {
-var1 = 0; /* is null */
-} else {
-var1 = 1; /* arg is null and recv is not */
-}
-if (var1){
-((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable ADoc(ADoc)>*/;
-} else {
-}
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#n_doc= for (self: Object, nullable ADoc) */
-void VIRTUAL_parser_prod__AConcreteInitPropdef__n_doc_61d(val* self, val* p0) {
-parser_prod__AConcreteInitPropdef__n_doc_61d(self, p0);
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#n_kwredef= for (self: AConcreteInitPropdef, nullable TKwredef) */
-void parser_prod__AConcreteInitPropdef__n_kwredef_61d(val* self, val* p0) {
-val* var_node /* var node: nullable TKwredef */;
-val* var /* : null */;
-short int var1 /* : Bool */;
-var_node = p0;
-self->attrs[COLOR_parser_nodes__AMethPropdef___n_kwredef].val = var_node; /* _n_kwredef on <self:AConcreteInitPropdef> */
-var = NULL;
-if (var_node == NULL) {
-var1 = 0; /* is null */
-} else {
-var1 = 1; /* arg is null and recv is not */
-}
-if (var1){
-((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable TKwredef(TKwredef)>*/;
-} else {
-}
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#n_kwredef= for (self: Object, nullable TKwredef) */
-void VIRTUAL_parser_prod__AConcreteInitPropdef__n_kwredef_61d(val* self, val* p0) {
-parser_prod__AConcreteInitPropdef__n_kwredef_61d(self, p0);
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#n_visibility= for (self: AConcreteInitPropdef, nullable AVisibility) */
-void parser_prod__AConcreteInitPropdef__n_visibility_61d(val* self, val* p0) {
-val* var_node /* var node: nullable AVisibility */;
-var_node = p0;
-self->attrs[COLOR_parser_nodes__AMethPropdef___n_visibility].val = var_node; /* _n_visibility on <self:AConcreteInitPropdef> */
-if (var_node == NULL) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Reciever is null", "src/parser/parser_prod.nit", 2562);
-exit(1);
-} else {
-((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:nullable AVisibility>*/;
-}
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#n_visibility= for (self: Object, nullable AVisibility) */
-void VIRTUAL_parser_prod__AConcreteInitPropdef__n_visibility_61d(val* self, val* p0) {
-parser_prod__AConcreteInitPropdef__n_visibility_61d(self, p0);
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#n_kwinit= for (self: AConcreteInitPropdef, TKwinit) */
-void parser_prod__AConcreteInitPropdef__n_kwinit_61d(val* self, val* p0) {
-val* var_node /* var node: TKwinit */;
-var_node = p0;
-self->attrs[COLOR_parser_nodes__AConcreteInitPropdef___n_kwinit].val = var_node; /* _n_kwinit on <self:AConcreteInitPropdef> */
-((void (*)(val*, val*))(var_node->class->vft[COLOR_parser_nodes__ANode__parent_61d]))(var_node, self) /* parent= on <var_node:TKwinit>*/;
-RET_LABEL:;
-}
-/* method parser_prod#AConcreteInitPropdef#n_kwinit= for (self: Object, TKwinit) */
-void VIRTUAL_parser_prod__AConcreteInitPropdef__n_kwinit_61d(val* self, val* p0) {
-parser_prod__AConcreteInitPropdef__n_kwinit_61d(self, p0);
-RET_LABEL:;
-}