-var11 = 1; /* easy <var_to:Int> isa OTHER*/
-if (!var11) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "lib/standard/kernel.nit", 256);
-exit(1);
-}
-var14 = var_i <= var_to;
-var9 = var14;
-goto RET_LABEL10;
-RET_LABEL10:(void)0;
-}
-var_ = var9;
-if (var9){
-var15 = ((val* (*)(val*, long))(var_array->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var_array, var_i) /* [] on <var_array:Array[nullable Object]>*/;
-var16 = ((long (*)(val*, val*, val*))(self->class->vft[COLOR_sorter__AbstractSorter__compare]))(self, var15, var_pivot) /* compare on <self:AbstractSorter[nullable Object]>*/;
-var17 = 0;
-{ /* Inline kernel#Int#<= (var16,var17) */
-/* Covariant cast for argument 0 (i) <var17:Int> isa OTHER */
-/* <var17:Int> isa OTHER */
-var20 = 1; /* easy <var17:Int> isa OTHER*/
-if (!var20) {
-fprintf(stderr, "Runtime error: %s (%s:%d)\n", "Cast failed", "lib/standard/kernel.nit", 256);
-exit(1);
-}
-var23 = var16 <= var17;
-var18 = var23;
-goto RET_LABEL19;
-RET_LABEL19:(void)0;
-}
-var8 = var18;
+var12 = 1; /* easy <var_to:Int> isa OTHER*/
+if (!var12) {
+var_class_name15 = type_kernel__Int.name;
+fprintf(stderr, "Runtime error: Cast failed. Expected `%s`, got `%s`", "OTHER", var_class_name15);
+fprintf(stderr, " (%s:%d)\n", "lib/standard/kernel.nit", 260);
+show_backtrace(1);
+}
+var16 = var_i <= var_to;
+var10 = var16;
+goto RET_LABEL11;
+RET_LABEL11:(void)0;
+}
+var_ = var10;
+if (var10){
+var17 = ((val* (*)(val*, long))(var_array->class->vft[COLOR_abstract_collection__SequenceRead___91d_93d]))(var_array, var_i) /* [] on <var_array:Array[nullable Object]>*/;
+var18 = ((long (*)(val*, val*, val*))(self->class->vft[COLOR_sorter__AbstractSorter__compare]))(self, var17, var_pivot) /* compare on <self:AbstractSorter[nullable Object]>*/;
+var19 = 0;
+{ /* Inline kernel#Int#<= (var18,var19) */
+/* Covariant cast for argument 0 (i) <var19:Int> isa OTHER */
+/* <var19:Int> isa OTHER */
+var22 = 1; /* easy <var19:Int> isa OTHER*/
+if (!var22) {
+var_class_name25 = type_kernel__Int.name;
+fprintf(stderr, "Runtime error: Cast failed. Expected `%s`, got `%s`", "OTHER", var_class_name25);
+fprintf(stderr, " (%s:%d)\n", "lib/standard/kernel.nit", 260);
+show_backtrace(1);
+}
+var26 = var18 <= var19;
+var20 = var26;
+goto RET_LABEL21;
+RET_LABEL21:(void)0;
+}
+var9 = var20;