[FFmpeg-devel] CONFIG_W64_DEMUXER and dead-code elimination

Hendrik Leppkes h.leppkes at gmail.com
Wed May 11 16:51:30 CEST 2016

On Wed, May 11, 2016 at 4:19 PM, Bruce Dawson
<brucedawson-at-google.com at ffmpeg.org> wrote:
> The error is:
>     wavdec.obj : error LNK2001: unresolved external symbol _ff_w64_guid_data
> This happens because the compiler does not recognize early enough
> that _ff_w64_guid_data is never actually needed, so it creates a reference
> to it.

This sort of construct is used all the time in our code, so I would
suggest to also report this to MS as a regression.
Its important to keep in mind that they introduced a new optimizer
just recently in the pre-release builds, so regressions are bound to
happen, and hopefully disappear by the time it is released.

Testing Update 3 right now, and possibly reacting to any changes it
might require other then reporting regressions to MS, seems very

- Hendrik

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