Re: [libvirt] [PATCH] fwrite: silence __wur without using inline
On 01/03/13 12:23, Eric Blake wrote:
The elided code was not using _GL_EXTERN_INLINE, but _GL_INLINE.
They
have different semantics, but I'm hard-pressed to say _which_ semantics
are right from just those names.
Standard C semantics. _GL_EXTERN_INLINE is C99/C11 extern inline.
_GL_INILNE is C99/C11 inline.
If I understand correctly, we _want_
the semantics where the inline function is _always_ inlined and never
emitted as a linkable entry point, but I'd have to refer back to C99 and
the gcc manual to see which use of inline and possible __attribute__
combinations guarantees that point.
Can't be done in Standard C, as far as I know.
With GNU C it can be done with __attribute__((__always_inline__)).
Why is it important that it not be a linkable entry point?
maybe it's worth adding a name _GL_ELIDABLE_INLINE into
m4/extern-inline.m4 to make it easier to use the results.
Sorry, I guess I don't see how this would work.
That is, I can see how _GL_ELIDABLE_INLINE would expand to
'inline __attribute__((__always_inline__))'
in GNU C, but what would it expand to in Standard C?
It can't be expanded to nothing, since you don't want
a linkable entry point, and it can't be expanded to 'static',
at least not in a header, because the resulting function
couldn't be called from an extern inline function.