[FFmpeg-devel] r12525 crashes with gcc 4.3.0 on mingw32, due to a bug in compiler

Mike Melanson mike
Fri Mar 21 21:51:04 CET 2008

M?ns Rullg?rd wrote:
> "Zuxy Meng" <zuxy.meng at gmail.com> writes:
>> Hi,
>> I just found that GCC 4.3.0 on MinGW32 incorrectly marks the
>> .text.unlikely section as "writable" instead of "executable", which
>> causes as to believe it should pad the section with zeros instead of
>> nops. The result is catastrophic.
> What instruction do zeros decode to?  On most CPUs I've seen, they are
> some nop or other.

Something like "add dx, [si+ax]", if memory servers. I saw it a lot when
I was playing with x86 debuggers.

x86_32 NOP is 0x90.

	-Mike Melanson

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