[Bug fortran/79876] [7 Regression] FAIL: libgomp.fortran/strassen.f90 -O execution test on x86_64-apple-darwin16

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79876

Thomas Koenig <tkoenig at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |7.0

--- Comment #2 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
(In reply to Dominique d'Humieres from comment #1)
> Revisions r242462 and r242518 are within the range.
> 
> The failure triggers also if the tests are compiled with -O0 or with
> -fno-frontend-optimize.

A few questions:

- Still happening after r245839 (which fixed a potential race condition)?

- What / where is the illegal instruction happening?  Is it in
  matmul_*_avx, matmul_*_avx2, ...?

- What CPU are you running?

- If you print __cpu_model.__cpu_vendor and __cpu_model.__cpu_features[0]
from a debugger, what is the output?

- What is the stack size for each thread?  Are you maybe running
  into a stack limitation?