[FFmpeg-devel] [RFC] insufficient VFP check?

Måns Rullgård mans
Sun Jan 17 00:51:31 CET 2010

Reimar D?ffinger <Reimar.Doeffinger at gmx.de> writes:

> On Sat, Jan 16, 2010 at 11:40:34PM +0000, M?ns Rullg?rd wrote:
>> Reimar D?ffinger <Reimar.Doeffinger at gmx.de> writes:
>> > Hello,
>> > the configure vfp check looks for
>> > fadds s0, s0, s0
>> > However, this detects VFP e.g. for
>> > -mcpu=cortex-a8 -mfpu=neon -mfloat-abi=softfp
>> > while actual compilation fails with e.g.
>> > libavcodec/arm/dsputil_vfp.S:160: Error: selected processor does not support `vmov r7,r8,s4,s5'
>> > So what is the right solution, replace the check with something
>> > like the failing instruction?
>> What configure line did you use?  It always works for me...
> Something a bit silly:
> ./configure --cross-prefix=armv7a-softfloat-linux-gnueabi- --extra-cflags="-mcpu=cortex-a8 -mfpu=neon -mfloat-abi=softfp" --arch=arm --cpu=cortex-a8
> However doesn't look silly enough to make it break that way..

You don't need the -mcpu in --extra-cflags, otherwise there's nothing
wrong with that configure line.  It is in fact what I use all the time.

M?ns Rullg?rd
mans at mansr.com

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