[FFmpeg-devel] [PATCH] The definition of av_always_inline with --enable-small or --disable-optimizations

[Martin Storsjö]

On Tue, 14 Dec 2010, Michael Niedermayer wrote:

> On Tue, Dec 14, 2010 at 11:28:36AM +0200, Martin Storsj? wrote:
> > Hi,
> > 
> > At the end of the configure script, we currently do this:
> > 
> > if enabled small || disabled optimizations; then
> >     echo "#undef  av_always_inline"  >> $TMPH
> >     echo "#define av_always_inline"  >> $TMPH
> > fi
> > 
> > This causes a lot of warnings when building with either of these 
> > configurations, warnings like this one:
> > 
> > ./libavutil/x86/bswap.h:32: warning: ?av_bswap16? defined but not used
> > 
> > These warnings can be silenced either by adding -Wno-unused-function to 
> > the cflags, or by changing the definition of av_always_inline for this 
> > case. Possible options are:
> > 
> > - empty, as currently, spewing lots of warnings
> > - inline (as opposed to the __attribute__((always_inline) used otherwise), 
> >   but that won't avoid all inlineing even if the user requested 
> >   --disable-optimizations
> 
> > - __attribute__((unused)), which seems to be supported since gcc 2.95
> 
> This would suppress unused warnings incorrectly

Only for builds with --disable-optimizations or for --enable-small. 
Currently, in those build configurations, it's really hard to see the 
relevant warnings since the console is totally spammed with the warnings 
for all the defined but unused static av_always_inline functions.

For all occurrances of av_always_inline functions in headers, I see no 
issue with __attribute__((unused)).

Would you prefer the version where av_always_inline is redefined as 
"inline" for --enable-small builds (but as __attribute__((unused)) for 
--disable-optimizations)?

// Martin