On Windows just installing libblas (with mkl) is not sufficient to make sure that CMake's find_package(BLAS REQUIRED) succeeds

[traversaro]

Solution to issue cannot be found in the documentation.

• I checked the documentation.

Issue

On Windows, just installing libblas with mkl backend is not sufficient to make sure that CMake's find_package(BLAS REQUIRED) succeeds.

For example, these fails with Could NOT find BLAS (missing: BLAS_LIBRARIES) error:

conda create -n blasmklcheck libblas=*=*mkl* cmake-package-check compilers cmake pkg-config ninja
conda activate blasmklcheck 
cmake-package-check BLAS

while these succeeds:

nda create -n blasdevelmklcheck blas-devel libblas=*=*mkl* cmake-package-check compilers cmake pkg-config ninja
conda activate blasdevelmklcheck 
cmake-package-check BLAS

Installed packages

(blasmklcheck) C:\Users\straversaro>conda list
# packages in environment at D:\miniforge3\envs\blasmklcheck:
#
# Name                    Version                   Build  Channel
bzip2                     1.0.8                hcfcfb64_5    conda-forge
c-compiler                1.7.0                hcfcfb64_1    conda-forge
ca-certificates           2024.2.2             h56e8100_0    conda-forge
clangdev                  5.0.0                   flang_3    conda-forge
cmake                     3.29.3               h75d51d9_0    conda-forge
cmake-package-check       0.0.4              pyh4af843d_0    conda-forge
compilers                 1.7.0                h57928b3_1    conda-forge
cxx-compiler              1.7.0                h91493d7_1    conda-forge
flang                     5.0.0           he025d50_20180525    conda-forge
flang_win-64              5.0.0           h13ae965_20180526    conda-forge
fortran-compiler          1.7.0                h9655429_1    conda-forge
intel-openmp              2024.1.0           h57928b3_965    conda-forge
jinja2                    3.1.4              pyhd8ed1ab_0    conda-forge
krb5                      1.21.2               heb0366b_0    conda-forge
libblas                   3.9.0              22_win64_mkl    conda-forge
libcurl                   8.7.1                hd5e4a3a_0    conda-forge
libexpat                  2.6.2                h63175ca_0    conda-forge
libffi                    3.4.2                h8ffe710_5    conda-forge
libflang                  5.0.0           h6538335_20180525    conda-forge
libglib                   2.80.2               h0df6a38_0    conda-forge
libhwloc                  2.10.0          default_h2fffb23_1000    conda-forge
libiconv                  1.17                 hcfcfb64_2    conda-forge
libintl                   0.22.5               h5728263_2    conda-forge
libsqlite                 3.45.3               hcfcfb64_0    conda-forge
libssh2                   1.11.0               h7dfc565_0    conda-forge
libuv                     1.48.0               hcfcfb64_0    conda-forge
libxml2                   2.12.6               hc3477c8_2    conda-forge
libzlib                   1.2.13               hcfcfb64_5    conda-forge
llvm-meta                 5.0.0                         0    conda-forge
markupsafe                2.1.5           py312he70551f_0    conda-forge
mkl                       2024.1.0           h66d3029_692    conda-forge
ninja                     1.12.1               hc790b64_0    conda-forge
openmp                    5.0.0                    vc14_1    conda-forge
openssl                   3.3.0                hcfcfb64_0    conda-forge
pcre2                     10.43                h17e33f8_0    conda-forge
pip                       24.0               pyhd8ed1ab_0    conda-forge
pkg-config                0.29.2            h2bf4dc2_1008    conda-forge
pthreads-win32            2.9.1                hfa6e2cd_3    conda-forge
python                    3.12.3          h2628c8c_0_cpython    conda-forge
python_abi                3.12                    4_cp312    conda-forge
setuptools                69.5.1             pyhd8ed1ab_0    conda-forge
tbb                       2021.12.0            h91493d7_0    conda-forge
tk                        8.6.13               h5226925_1    conda-forge
tzdata                    2024a                h0c530f3_0    conda-forge
ucrt                      10.0.22621.0         h57928b3_0    conda-forge
vc                        14.3                hcf57466_18    conda-forge
vc14_runtime              14.38.33130         h82b7239_18    conda-forge
vs2015_runtime            14.38.33130         hcb4865c_18    conda-forge
vs2019_win-64             19.29.30139         he1865b1_18    conda-forge
vswhere                   3.1.4                h57928b3_0    conda-forge
wheel                     0.43.0             pyhd8ed1ab_1    conda-forge
xz                        5.2.6                h8d14728_0    conda-forge
zstd                      1.5.6                h0ea2cb4_0    conda-forge

Environment info

(blasmklcheck) C:\Users\straversaro>conda info

     active environment : blasmklcheck
    active env location : D:\miniforge3\envs\blasmklcheck
            shell level : 1
       user config file : C:\Users\straversaro\.condarc
 populated config files : D:\miniforge3\.condarc
                          C:\Users\straversaro\.condarc
          conda version : 23.11.0
    conda-build version : 24.3.0
         python version : 3.10.13.final.0
                 solver : libmamba (default)
       virtual packages : __archspec=1=x86_64
                          __conda=23.11.0=0
                          __cuda=12.3=0
                          __win=0=0
       base environment : D:\miniforge3  (writable)
      conda av data dir : D:\miniforge3\etc\conda
  conda av metadata url : None
           channel URLs : https://conda.anaconda.org/robostack-staging/win-64
                          https://conda.anaconda.org/robostack-staging/noarch
                          https://conda.anaconda.org/conda-forge/win-64
                          https://conda.anaconda.org/conda-forge/noarch
          package cache : D:\miniforge3\pkgs
                          C:\Users\straversaro\.conda\pkgs
                          C:\Users\straversaro\AppData\Local\conda\conda\pkgs
       envs directories : D:\miniforge3\envs
                          C:\Users\straversaro\.conda\envs
                          C:\Users\straversaro\AppData\Local\conda\conda\envs
               platform : win-64
             user-agent : conda/23.11.0 requests/2.31.0 CPython/3.10.13 Windows/10 Windows/10.0.22631 solver/libmamba conda-libmamba-solver/23.12.0 libmambapy/1.5.5
          administrator : False
             netrc file : None
           offline mode : False

[traversaro]

See conda-forge/conda-forge.github.io#2171 for the original discussion.

PRs that failed with Could NOT find BLAS (missing: BLAS_LIBRARIES) due to this:

• Win build colmap-feedstock#4 (comment)
• add Windows suitesparse-feedstock#92

[isuruf]

I didn't realize you were using libblas with MKL instead of netlib. Then you do need blas-devel.