[Bug c++/98364] [modules] unnneded global constructors are emitted for a module

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98364

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |NEW
            Summary|[modules] global            |[modules] unnneded global
                   |constructor emission        |constructors are emitted
                   |                            |for a module
           Severity|normal                      |enhancement

--- Comment #8 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed:
;; Function (static initializers for hello.cc) (_ZGIW5helloEv)
;; enabled by -tree-original


{
  static bool __in_chrg;

    static bool __in_chrg;
  if (__in_chrg)
    {
      return;
    }
  <<cleanup_point <<< Unknown tree: expr_stmt
  (void) (__in_chrg = 1) >>>>>;
}


In main-hello.cc.005t.original.

The code comes from start_objects in cp/decl2.c:


  if (module_init > 0)
    {
      // 'static bool __in_chrg = false;
      // if (__inchrg) return;
      // __inchrg = true
      tree var = build_lang_decl (VAR_DECL, in_charge_identifier,
                                  boolean_type_node);
      DECL_CONTEXT (var) = fndecl;
      DECL_ARTIFICIAL (var) = true;
      TREE_STATIC (var) = true;
      pushdecl (var);
      cp_finish_decl (var, NULL_TREE, false, NULL_TREE, 0);

      tree if_stmt = begin_if_stmt ();
      finish_if_stmt_cond (var, if_stmt);
      finish_return_stmt (NULL_TREE);
      finish_then_clause (if_stmt);
      finish_if_stmt (if_stmt);

      tree assign = build2 (MODIFY_EXPR, boolean_type_node,
                            var, boolean_true_node);
      TREE_SIDE_EFFECTS (assign) = true;
      finish_expr_stmt (assign);
    }
  if (module_init)
    module_add_import_initializers ();

Maybe if there are no initializers, maybe we should not create the global init.