Issue with main function expansion and Ada

[Nicolas Roche <roche at adacore dot com>]

Hi,

I am currently working on having GCC 4.1 working on mingw with ZCX 
exceptions and I got the following issue with Ada and the constructors:

On windows a __main function in charge of calling the constructors (so 
that register_frame_info is called)  is used. This function is called by 
main and the call is added by expand_main_function in function.c.

expand_main_function is called in tree_expand_cfg (cfgexpand.c) only if 
the current function is the main one :

...
/* If this function is `main', emit a call to `__main'
    to run global initializers, etc.  */
 if (DECL_NAME (current_function_decl)
     && MAIN_NAME_P (DECL_NAME (current_function_decl))
     && DECL_FILE_SCOPE_P (current_function_decl))
   expand_main_function ();
...

The issue in Ada is that the result of DECL_NAME for the main function 
is not "main" but somethind like "_ada_main__main" because the main 
function is in a package called ada_main (generated by the binder).

The consequence is that expand_main_function will never be called (and 
so my exception tables not registered :-().

Using DECL_ASSEMBLER_NAME instead of DECL_NAME solves the issue as the 
exported name of that function will be "main".

Is this change seems reasonable ?
(If yes I will do a complete test before submiting the patch)

Note that this affect potentially all the platforms that use __main to 
call the constructors (so I think mainly non elf platforms ..).

Thanks in advance for your answers

Nicolas