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.
