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* libffi misidentifies certain older Intel CPU capabilites
@ 2018-05-26 18:42 Michael Shell
  0 siblings, 0 replies; only message in thread
From: Michael Shell @ 2018-05-26 18:42 UTC (permalink / raw)
  To: libffi-discuss; +Cc: green



  Anthony and other libffi developers/users,

Over at the Linux From Scratch site, we've been seeing users get bitten
by a bug in libffi where it thinks certain Intel processors have
capabilites they actually don't which results in Illegal Instruction
errors. Specifically, gcc, or at least the most recent version of it,
is employing the vmovq instruction on CPUs that don't support it,
e.g., Celeron G530 and G640T:

http://lists.linuxfromscratch.org/pipermail/lfs-support/2018-May/051993.html
http://lists.linuxfromscratch.org/pipermail/lfs-support/2018-May/052029.html

Solved here:
http://lists.linuxfromscratch.org/pipermail/lfs-support/2018-May/052008.html


So, libffi needs to disable support for avx and aes instructions on
Intel CPUs that don't support them. Just thought I'd send you a heads
up on this issue.


  Cheers and thanks,

  Mike Shell

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