Re: #50205 - GCallback should not be a void pointer

[Owen Taylor <otaylor redhat com>]

Tim Janik <timj gtk org> writes:

> On 26 Mar 2001, Owen Taylor wrote:
> 
> > 
> > Having GCallback be a void * is particularly evil because
> > casts between void * and are function pointer are not allowed
> > by ANSI C, but gcc -Wall doesn't warn about them.
> > 
> > So, this is just an open invitation for people to write 
> > code that is not portable to compilers other than gcc.
> > 
> > Providing a real function pointer typedef for GCallback
> > will force people to use the G_CALLBACK() macro.
> > 
> > Can I commit?
> 
> what's bad about typedef void (*GCallback) (); special cased
> for non-c++ use use?

 a) Special casing for C++ is evil. For example, older versions of
    G++ are buggy and treat empty parens inside extern "C" in the C 
    manner, unless -pedantic is specified. This causes code compiled
    with -pendantic to have different mangling.
 b) Empty parens to mean "unspecified" is IIRC explicitely deprecated
    in C99.

Regards,
                                        Owen