title: libraries mkl_rt, openblas, lapack not found while installing scipy - How to change flags for libraries
body: <p>I am new to python and pip ecosystem. I am trying to install scikit-image and it is installing scipy as a dependency I suppose. I am using macOS 11.1 and I know that support for this version is not great since it just released but I was able to install packages like numpy, pillow just by changing few flags(LDFLAGS, CPPFLAGS).</p>
  <p>Can someone tell me if I can resolve below installation errors by changing few configurations or not?</p>
  <p>I already have openblas, mkl_rt libraries installed.</p>
  <pre><code>(trial) ~/.virtualenvs/trial python -m pip install scikit-image                                       
  Collecting scikit-image
    Using cached scikit-image-0.17.2.tar.gz (29.8 MB)
  Requirement already satisfied: numpy&gt;=1.15.1 in ./lib/python3.6/site-packages (from scikit-image) (1.19.4)
  Collecting scipy&gt;=1.0.1
    Using cached scipy-1.5.4.tar.gz (25.2 MB)
    Installing build dependencies ... done
    Getting requirements to build wheel ... done
      Preparing wheel metadata ... error
      ERROR: Command errored out with exit status 1:
       command: /Users/myusername/.virtualenvs/trial/bin/python /Users/myusername/.virtualenvs/trial/lib/python3.6/site-packages/pip/_vendor/pep517/_in_process.py prepare_metadata_for_build_wheel /var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/tmpk55uptaz
           cwd: /private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-install-1v5ec7uf/scipy
      Complete output (137 lines):
      lapack_opt_info:
      lapack_mkl_info:
      customize UnixCCompiler
        libraries mkl_rt not found in ['/Users/myusername/.virtualenvs/trial/lib', '/usr/local/lib', '/usr/lib']
        NOT AVAILABLE
      
      openblas_lapack_info:
      customize UnixCCompiler
      customize UnixCCompiler
        libraries openblas not found in ['/Users/myusername/.virtualenvs/trial/lib', '/usr/local/lib', '/usr/lib']
        NOT AVAILABLE
      
      openblas_clapack_info:
      customize UnixCCompiler
      customize UnixCCompiler
        libraries openblas,lapack not found in ['/Users/myusername/.virtualenvs/trial/lib', '/usr/local/lib', '/usr/lib']
        NOT AVAILABLE
      
      atlas_3_10_threads_info:
      Setting PTATLAS=ATLAS
      customize UnixCCompiler
        libraries tatlas,tatlas not found in /Users/myusername/.virtualenvs/trial/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /Users/myusername/.virtualenvs/trial/lib
      customize UnixCCompiler
        libraries tatlas,tatlas not found in /usr/local/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /usr/local/lib
      customize UnixCCompiler
        libraries tatlas,tatlas not found in /usr/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /usr/lib
      &lt;class 'numpy.distutils.system_info.atlas_3_10_threads_info'&gt;
        NOT AVAILABLE
      
      atlas_3_10_info:
      customize UnixCCompiler
        libraries satlas,satlas not found in /Users/myusername/.virtualenvs/trial/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /Users/myusername/.virtualenvs/trial/lib
      customize UnixCCompiler
        libraries satlas,satlas not found in /usr/local/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /usr/local/lib
      customize UnixCCompiler
        libraries satlas,satlas not found in /usr/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /usr/lib
      &lt;class 'numpy.distutils.system_info.atlas_3_10_info'&gt;
        NOT AVAILABLE
      
      atlas_threads_info:
      Setting PTATLAS=ATLAS
      customize UnixCCompiler
        libraries ptf77blas,ptcblas,atlas not found in /Users/myusername/.virtualenvs/trial/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /Users/myusername/.virtualenvs/trial/lib
      customize UnixCCompiler
        libraries ptf77blas,ptcblas,atlas not found in /usr/local/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /usr/local/lib
      customize UnixCCompiler
        libraries ptf77blas,ptcblas,atlas not found in /usr/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /usr/lib
      &lt;class 'numpy.distutils.system_info.atlas_threads_info'&gt;
        NOT AVAILABLE
      
      atlas_info:
      customize UnixCCompiler
        libraries f77blas,cblas,atlas not found in /Users/myusername/.virtualenvs/trial/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /Users/myusername/.virtualenvs/trial/lib
      customize UnixCCompiler
        libraries f77blas,cblas,atlas not found in /usr/local/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /usr/local/lib
      customize UnixCCompiler
        libraries f77blas,cblas,atlas not found in /usr/lib
      customize UnixCCompiler
        libraries lapack_atlas not found in /usr/lib
      &lt;class 'numpy.distutils.system_info.atlas_info'&gt;
        NOT AVAILABLE
      
      lapack_info:
      customize UnixCCompiler
        libraries lapack not found in ['/Users/myusername/.virtualenvs/trial/lib', '/usr/local/lib', '/usr/lib']
        NOT AVAILABLE
      
      lapack_src_info:
        NOT AVAILABLE
      
        NOT AVAILABLE
      
      setup.py:462: UserWarning: Unrecognized setuptools command ('dist_info --egg-base /private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-modern-metadata-tssa7s05'), proceeding with generating Cython sources and expanding templates
        ' '.join(sys.argv[1:])))
      Running from SciPy source directory.
      /private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-build-env-_26ufpkr/overlay/lib/python3.6/site-packages/numpy/distutils/system_info.py:624: UserWarning:
          Atlas (http://math-atlas.sourceforge.net/) libraries not found.
          Directories to search for the libraries can be specified in the
          numpy/distutils/site.cfg file (section [atlas]) or by setting
          the ATLAS environment variable.
        self.calc_info()
      /private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-build-env-_26ufpkr/overlay/lib/python3.6/site-packages/numpy/distutils/system_info.py:624: UserWarning:
          Lapack (http://www.netlib.org/lapack/) libraries not found.
          Directories to search for the libraries can be specified in the
          numpy/distutils/site.cfg file (section [lapack]) or by setting
          the LAPACK environment variable.
        self.calc_info()
      /private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-build-env-_26ufpkr/overlay/lib/python3.6/site-packages/numpy/distutils/system_info.py:624: UserWarning:
          Lapack (http://www.netlib.org/lapack/) sources not found.
          Directories to search for the sources can be specified in the
          numpy/distutils/site.cfg file (section [lapack_src]) or by setting
          the LAPACK_SRC environment variable.
        self.calc_info()
      Traceback (most recent call last):
        File &quot;/Users/myusername/.virtualenvs/trial/lib/python3.6/site-packages/pip/_vendor/pep517/_in_process.py&quot;, line 280, in &lt;module&gt;
          main()
        File &quot;/Users/myusername/.virtualenvs/trial/lib/python3.6/site-packages/pip/_vendor/pep517/_in_process.py&quot;, line 263, in main
          json_out['return_val'] = hook(**hook_input['kwargs'])
        File &quot;/Users/myusername/.virtualenvs/trial/lib/python3.6/site-packages/pip/_vendor/pep517/_in_process.py&quot;, line 133, in prepare_metadata_for_build_wheel
          return hook(metadata_directory, config_settings)
        File &quot;/private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-build-env-_26ufpkr/overlay/lib/python3.6/site-packages/setuptools/build_meta.py&quot;, line 161, in prepare_metadata_for_build_wheel
          self.run_setup()
        File &quot;/private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-build-env-_26ufpkr/overlay/lib/python3.6/site-packages/setuptools/build_meta.py&quot;, line 254, in run_setup
          self).run_setup(setup_script=setup_script)
        File &quot;/private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-build-env-_26ufpkr/overlay/lib/python3.6/site-packages/setuptools/build_meta.py&quot;, line 145, in run_setup
          exec(compile(code, __file__, 'exec'), locals())
        File &quot;setup.py&quot;, line 583, in &lt;module&gt;
          setup_package()
        File &quot;setup.py&quot;, line 579, in setup_package
          setup(**metadata)
        File &quot;/private/var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/pip-build-env-_26ufpkr/overlay/lib/python3.6/site-packages/numpy/distutils/core.py&quot;, line 135, in setup
          config = configuration()
        File &quot;setup.py&quot;, line 477, in configuration
          raise NotFoundError(msg)
      numpy.distutils.system_info.NotFoundError: No lapack/blas resources found. Note: Accelerate is no longer supported.
      ----------------------------------------
  ERROR: Command errored out with exit status 1: /Users/myusername/.virtualenvs/trial/bin/python /Users/myusername/.virtualenvs/trial/lib/python3.6/site-packages/pip/_vendor/pep517/_in_process.py prepare_metadata_for_build_wheel /var/folders/ss/d2f4tvvn7fzc42ls4hbrw06h0000gn/T/tmpk55uptaz Check the logs for full command output.
  </code></pre>