Failed tests when compiling with openmp

[jalvesz]

Description

I tested building and running the tests, including OpenMP support, by including the flag:

cmake -B build -G Ninja -DBUILD_TESTING=on -DCMAKE_Fortran_FLAGS=-fopenmp -DCMAKE_MAXIMUM_RANK:String=4 -DCMAKE_BUILD_TYPE=Release -DCMAKE_Fortran_COMPILER=gfortran
cmake --build build
ctest --test-dir build/test

several of the tests failed:

86% tests passed, 11 tests failed out of 77

Label Time Summary:
quadruple_precision    =   0.17 sec*proc (2 tests)

Total Test time (real) =  12.68 sec

The following tests FAILED:
         12 - chaining_maps (SEGFAULT)
         13 - open_maps (SEGFAULT)
         14 - maps (SEGFAULT)
         15 - intrinsics (Failed)
         30 - linalg_pseudoinverse (Failed)
         38 - blas_lapack (Failed)
         43 - sorting (Exit code 0xc0000374
)
         47 - mean (Failed)
         59 - string_intrinsic (Failed)
         64 - string_to_number (Failed)
         69 - simps (Failed)

         64 - string_to_number (Failed)
         69 - simps (Failed)
         64 - string_to_number (Failed)
         69 - simps (Failed)
         64 - string_to_number (Failed)
         69 - simps (Failed)

I wonder if one of the CI jobs should include OpenMP in order to catch such behaviours early ?

Expected Behaviour

Should pass

Version of stdlib

master

Platform and Architecture

Windows / gfortran 14.2.0

Additional Information

No response

[jvdp1]

Strange that it failed on some procedures like blas_lapack or sorting. I agree that we should include OpenMP in at least one of the CI jobs.

[jalvesz]

I was looking at the intrinsics test and saw that they fail for sum and dot_product for xdp. I saw that there is a tolerance issue, for instance, if I print the tolerance and relative errors here

https://github.com/fortran-lang/stdlib/blob/60d0a769216322243e28a63b92ed7668d2df80d5/test/intrinsics/test_intrinsics.fypp#L213C1-L218C87

adding a print *, '${t}$ dot err:', tolerance, err(1:3)

I get without openmp:
real(xdp) dot err: 1.08420217248550443401E-0017 3.25260651745651330202E-0019 0.00000000000000000000 0.00000000000000000000

With openmp:
real(xdp) dot err: 1.08420217248550443401E-0017 2.22044604925031308085E-0016 0.00000000000000000000 5.55111512312578270212E-0016

For the latter, the errors seems to be funnily close to epsilon(0.d0) = 2.220446049250313E-016 ... I'm intrigued here, I wonder if the other tests might be suffering from something similar.