Merge: add attribute annotation `noinit` to skip the attribute in inits

~~~.rb
class Toto
   var tata: Int is noinit
   var tutu: String
end
var t = new Toto("hello") # only tutu in the constructor
~~~

Pull-Request: #600
Reviewed-by: Lucas Bajolet <r4pass@hotmail.com>
Reviewed-by: Alexandre Terrasa <alexandre@moz-code.org>

diff --combined src/abstract_compiler.nit
index a2c08de,c4ddcb0..8015a5a
--- 1/src/abstract_compiler.nit
--- 2/src/abstract_compiler.nit
+++ b/src/abstract_compiler.nit
@@@ -578,40 -578,7 +578,40 @@@ abstract class AbstractCompile
        protected fun compile_header_structs is abstract
  
        # Declaration of structures for nitni undelying the FFI
 -      protected fun compile_nitni_structs is abstract
 +      protected fun compile_nitni_structs
 +      do
 +              self.header.add_decl """
 +/* Native reference to Nit objects */
 +/* This structure is used to represent every Nit type in extern methods and custom C code. */
 +struct nitni_ref {
 +      struct nitni_ref *next,
 +              *prev; /* adjacent global references in global list */
 +      int count; /* number of time this global reference has been marked */
 +};
 +
 +/* List of global references from C code to Nit objects */
 +/* Instanciated empty at init of Nit system and filled explicitly by user in C code */
 +struct nitni_global_ref_list_t {
 +      struct nitni_ref *head, *tail;
 +};
 +extern struct nitni_global_ref_list_t *nitni_global_ref_list;
 +
 +/* Initializer of global reference list */
 +extern void nitni_global_ref_list_init();
 +
 +/* Intern function to add a global reference to the list */
 +extern void nitni_global_ref_add( struct nitni_ref *ref );
 +
 +/* Intern function to remove a global reference from the list */
 +extern void nitni_global_ref_remove( struct nitni_ref *ref );
 +
 +/* Increase count on an existing global reference */
 +extern void nitni_global_ref_incr( struct nitni_ref *ref );
 +
 +/* Decrease count on an existing global reference */
 +extern void nitni_global_ref_decr( struct nitni_ref *ref );
 +"""
 +      end
  
        # Generate the main C function.
        # This function:
@@@ -721,9 -688,6 +721,9 @@@
  
                v.add("glob_argc = argc; glob_argv = argv;")
                v.add("initialize_gc_option();")
 +
 +              v.add "initialize_nitni_global_refs();"
 +
                var main_type = mainmodule.sys_type
                if main_type != null then
                        var mainmodule = v.compiler.mainmodule
@@@ -783,67 -747,6 +783,67 @@@
                v.add("\}")
        end
  
 +      # Copile all C functions related to the [incr|decr]_ref features of the FFI
 +      fun compile_nitni_global_ref_functions
 +      do
 +              var v = self.new_visitor
 +              v.add """
 +struct nitni_global_ref_list_t *nitni_global_ref_list;
 +void initialize_nitni_global_refs() {
 +      nitni_global_ref_list = (struct nitni_global_ref_list_t*)nit_alloc(sizeof(struct nitni_global_ref_list_t));
 +      nitni_global_ref_list->head = NULL;
 +      nitni_global_ref_list->tail = NULL;
 +}
 +
 +void nitni_global_ref_add( struct nitni_ref *ref ) {
 +      if ( nitni_global_ref_list->head == NULL ) {
 +              nitni_global_ref_list->head = ref;
 +              ref->prev = NULL;
 +      } else {
 +              nitni_global_ref_list->tail->next = ref;
 +              ref->prev = nitni_global_ref_list->tail;
 +      }
 +      nitni_global_ref_list->tail = ref;
 +
 +      ref->next = NULL;
 +}
 +
 +void nitni_global_ref_remove( struct nitni_ref *ref ) {
 +      if ( ref->prev == NULL ) {
 +              nitni_global_ref_list->head = ref->next;
 +      } else {
 +              ref->prev->next = ref->next;
 +      }
 +
 +      if ( ref->next == NULL ) {
 +              nitni_global_ref_list->tail = ref->prev;
 +      } else {
 +              ref->next->prev = ref->prev;
 +      }
 +}
 +
 +extern void nitni_global_ref_incr( struct nitni_ref *ref ) {
 +      if ( ref->count == 0 ) /* not registered */
 +      {
 +              /* add to list */
 +              nitni_global_ref_add( ref );
 +      }
 +
 +      ref->count ++;
 +}
 +
 +extern void nitni_global_ref_decr( struct nitni_ref *ref ) {
 +      if ( ref->count == 1 ) /* was last reference */
 +      {
 +              /* remove from list */
 +              nitni_global_ref_remove( ref );
 +      }
 +
 +      ref->count --;
 +}
 +"""
 +      end
 +
        # List of additional files required to compile (FFI)
        var extern_bodies = new Array[ExternFile]
  
@@@ -2178,7 -2081,7 +2178,7 @@@ redef class AClassde
                        var i = 1
                        # Collect undefined attributes
                        for npropdef in self.n_propdefs do
-                               if npropdef isa AAttrPropdef and npropdef.n_expr == null then
+                               if npropdef isa AAttrPropdef and npropdef.n_expr == null and not npropdef.noinit then
                                        v.write_attribute(npropdef.mpropdef.mproperty, recv, arguments[i])
                                        i += 1
                                end