[FFmpeg-devel] [FFmpeg-cvslog] r11100 - in trunk/libavcodec/i386: cavsdsp_mmx.c dsputil_mmx.c dsputil_mmx.h h264dsp_mmx.c mpegvideo_mmx.c vc1dsp_mmx.c

Uoti Urpala uoti.urpala
Sat Dec 1 20:26:33 CET 2007

On Sat, 2007-12-01 at 11:57 -0700, Loren Merritt wrote:
> On Sat, 1 Dec 2007, Uoti Urpala wrote:
> > It would be interesting to see the results with full visibility
> > information, but I guess you don't have that available. It should give
> > for each access the advantage that adding -fvisibility gives over just
> > -Bsymbolic for accesses to symbols defined in the same file, so the
> > extra benefit would depend on how many uses there are of non-static
> > symbols defined in the same file vs symbols defined in another file.
> What is full visibility information?
> Why does -fvisibility apply only to symbols uses in the same file, and 
> what is the alternative that applies to all symbols?

-fvisibility cannot apply to declarations for things defined in other
files because files will very likely include declarations for symbols
which are NOT defined in the same library (such as libc functions). See

> AFAICT, x264's visibility situation is very simple: One pragma in x264.h 
> to mark the api as public, and gcc -fvisibility to mark everything else as 
> hidden.

That'll mark all the symbols hidden, but the generated code still won't
access them directly except those defined in the same translation unit.

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