[FFmpeg-devel] CONFIG_W64_DEMUXER and dead-code elimination

[Hendrik Leppkes]

On Sat, Apr 23, 2016 at 1:02 AM, Bruce Dawson
<brucedawson-at-google.com at ffmpeg.org> wrote:
> I've noticed that when CONFIG_W64_DEMUXER is defined to zero that ffmpeg
> compiles in a reference to ff_w64_guid_data but doesn't not link w64.o
> (which defines that symbol).
>
> This normally works because most optimizers discard the reference
> to ff_w64_guid_data early enough to not cause a linker failure. However
> this assumption means that /Od (debug, unoptimized) and /GL (Link Time Code
> Generation - super optimized) builds with VC++ don't work.
>

We require dead code elimination to be available in all build modes,
therefor such build settings that do not have it are not supported.
This is not the only place that uses this, and its a design decision
to rely on it, therefor we won't be accepting patches to change that
at this time, sorry.

- Hendrik