[FFmpeg-devel] [PATCH]Remove test for cpuid instruction from cpuid.c

Carl Eugen Hoyos cehoyos
Sun Nov 23 14:45:07 CET 2008


M?ns Rullg?rd <mans <at> mansr.com> writes:

> >> cpuid is an ia32 instruction that was added for later 80486 processors. I 
> >> propose to remove the check for its existence from i386/cpuid.c.
> >> ffmpeg can still be compiled for 80386 with --disable-mmx.
> >>
> >> (Fixes compilation with icc 11.0)
> >>
> >> Please comment, Carl Eugen
> >
> > Iam against this (which is effectitly droping support for 386 & 486 CPU
> > for normal binary ffmpeg packages)

True, but is there really an ia32 system without cpuid that runs a distribution
where such a package can be installed?

> The only 486 still in existence I'm aware of is the one on-board the
> Hubble space telescope.  Do you suppose they run FFmpeg there?

Please note that most 80486 processors would still be supported;-)

You did already comment on issue 709: The application crashes after return - I
don't know if it's really the stack (debugging is, however, impossible), but I
reported the problem to intel and they "escalated" the problem. IMO, that just
means it will be tested next time when a new version of the compiler will be

I will copy the assembly sources into issue 709: It would be nice if somebody
who actually understands the code could comment there.

Carl Eugen

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