i386 clang optimisation problem with stack alignment

[Tijl Coosemans]

Hi,

I've attached a small test program extracted from multimedia/gstreamer-ffmpeg
(libavcodec/h264_cabac.c:ff_h264_init_cabac_states(H264Context *h)).

When you compile and run it like this on FreeBSD/i386, it results in a
SIGBUS:

% cc -o paddd paddd.c -O3 -msse2 -fPIE -fomit-frame-pointer 
% ./paddd
Bus error

The reason is this instruction where %esp isn't 16-byte aligned:
paddd   (%esp), %xmm7

Is this an upstream bug or is this because of local changes (to make the
stack 4 byte aligned by default or something)?
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