On 12/06/14 12:30, Jonathan Wakely wrote:
On 12 June 2014 01:42, Nikos Chantziaras <realnc@xxxxxxxxx> wrote:
On 12/06/14 03:31, Jonathan Wakely wrote:
On 11 June 2014 23:36, Nikos Chantziaras wrote:
According to the documentation:
https://gcc.gnu.org/onlinedocs/gcc-4.8.2/gcc/Function-Attributes.html#Function-Attributes
and more specific, the example about the visibility attribute:
void __attribute__ ((visibility ("protected")))
f () { /* Do something. */; }
doesn't work for me. I have this C++ function prototype:
const SDL_AudioSpec& __attribute__((visibility("default")))
spec();
Compiling this with g++ 4.8.2 gives me:
warning: 'visibility' attribute ignored on non-class types
I think the attribute binds to the return type here, which is a
reference (not a class type) so can't be given visibility.
This applies the attribute to the function, not the return type:
const SDL_AudioSpec& spec() __attribute__((visibility("hidden")));
I've found that this also works:
__attribute__((visibility("hidden"))) const SDL_AudioSpec& spec();
The only one that doesn't, is the documented one :-/ Documentation bug?
No, the example in the documentation is a function with a void return,
and in that case the attribute binds to the function not the return
type.
That can't be. This works:
int __attribute__((visibility("hidden"))) spec();
spec() is indeed hidden, so the attribute is not applied to the return
type at all (if that was even possible; how can you hide a return type.)
