from pgfogli =at= gmx =dot= com

gsl 2.2.1 linalg test fails with gcc (4.9.4 and later) and -mavx :
 
======================================
   gsl 2.2.1: linalg/test-suite.log
======================================
# TOTAL: 1
# PASS:  0
# SKIP:  0
# XFAIL: 0
# FAIL:  1
# XPASS: 0
# ERROR: 0
.. contents:: :depth: 2
FAIL: test
==========
FAIL: cholesky_decomp unscaled hilbert rcond: (  7,  7): 1.01502759282973088e-09   1.01502759382300005e-09
 (1.01502759282973088e-09 observed vs 1.01502759382300005e-09 expected) [272191]
FAIL: cholesky_decomp unscaled hilbert rcond: (  8,  8): 2.95222156993476919e-11   2.95222163060200025e-11
 (2.95222156993476919e-11 observed vs 2.95222163060200025e-11 expected) [272433]
FAIL: pcholesky_invert unscaled hilbert (  4,  4)[0,2]: -2.55795384873636067e-13                        0
 (-2.55795384873636067e-13 observed vs 0 expected) [533911]
FAIL: mcholesky_invert unscaled hilbert (  4,  4)[0,2]: -2.55795384873636067e-13                        0
 (-2.55795384873636067e-13 observed vs 0 expected) [672592]
 
 
The test fails on macOS 10.12.1 Sierra (Intel Core i7 Hasswell) with gcc (4.9.4, 5.4.0 and 6.2.0)
and clang (3.9.0) integrated assembler from MacPorts when given the compiler option -mavx.
I tested several compiler options and the failure seems triggered by -mavx.
For example the test pass with -mno-avx -mavx2.
I was able to reproduce the problem under cygwin with gcc 5.4.0 .
The test pass with gcc 4.8.5 under Linux (2.6.32 kernel, Intel Xeon E5 Sandy Bridge).
Unfortunately I do not have a more recent Linux/gcc at hand.