[PATCH] iWMMXt support was Re: [Ffmpeg-devel] iWMMXt support

Reimar Döffinger Reimar.Doeffinger
Thu Mar 15 10:44:30 CET 2007

On Thu, Mar 15, 2007 at 12:10:56AM +0100, Guillaume POIRIER wrote:
> Couldn't be done in the same way as we do Altivec support detection on 
> Linux?
> The idea is simple: install a signal handler for SIGILL, try to
> exectute an iWMMXt instruction, and if it triggers a SIGILL, then that
> means that no support is there, otherwise, iWMMXt is available.

And that one is still broken. It sent a patch to make it restore at
least the signal handler again to its original value, but it was
suggested to remove the whole hack instead. Many months later, this
completely broken code remains unchanged.
Changing a global attribute that can't be done in a thread-safe way from
a library is really evil anyway.

Reimar D?ffinger

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