BUILD: Remove Accelerate support (#15759)

Remove support for Apple Accelerate, since it is buggy. A build error should
occur on most or all setups if linked against Accelerate. Test or import failures
should occur on setups where Accelerate is picked up dynamically.

Co-authored-by: Warren Weckesser <warren.weckesser@gmail.com>

1 files changed, 22 insertions, 4 deletions

diff --git a/numpy/distutils/system_info.py b/numpy/distutils/system_info.py
index 3a6a7b29d..df82683dc 100644
--- a/numpy/distutils/system_info.py
+++ b/numpy/distutils/system_info.py
@@ -362,6 +362,22 @@ default_src_dirs = [_m for _m in default_src_dirs if os.path.isdir(_m)]
 so_ext = get_shared_lib_extension()
 
 
+def is_symlink_to_accelerate(filename):
+    accelpath = '/System/Library/Frameworks/Accelerate.framework'
+    return (sys.platform == 'darwin' and os.path.islink(filename) and
+            os.path.realpath(filename).startswith(accelpath))
+
+
+_accel_msg = (
+    'Found {filename}, but that file is a symbolic link to the '
+    'MacOS Accelerate framework, which is not supported by NumPy. '
+    'You must configure the build to use a different optimized library, '
+    'or disable the use of optimized BLAS and LAPACK by setting the '
+    'environment variables NPY_BLAS_ORDER="" and NPY_LAPACK_ORDER="" '
+    'before building NumPy.'
+)
+
+
 def get_standard_file(fname):
     """Returns a list of files named 'fname' from
     1) System-wide directory (directory-location of this module)
@@ -427,7 +443,6 @@ def get_info(name, notfound_action=0):
           'blis': blis_info,                  # use blas_opt instead
           'lapack_mkl': lapack_mkl_info,      # use lapack_opt instead
           'blas_mkl': blas_mkl_info,          # use blas_opt instead
-          'accelerate': accelerate_info,      # use blas_opt instead
           'openblas64_': openblas64__info,
           'openblas64__lapack': openblas64__lapack_info,
           'openblas_ilp64': openblas_ilp64_info,
@@ -919,6 +934,9 @@ class system_info:
             for prefix in lib_prefixes:
                 p = self.combine_paths(lib_dir, prefix + lib + ext)
                 if p:
+                    # p[0] is the full path to the binary library file.
+                    if is_symlink_to_accelerate(p[0]):
+                        raise RuntimeError(_accel_msg.format(filename=p[0]))
                     break
             if p:
                 assert len(p) == 1
@@ -1650,8 +1668,8 @@ def get_atlas_version(**config):
 
 class lapack_opt_info(system_info):
     notfounderror = LapackNotFoundError
-    # List of all known BLAS libraries, in the default order
-    lapack_order = ['mkl', 'openblas', 'flame', 'atlas', 'accelerate', 'lapack']
+    # List of all known LAPACK libraries, in the default order
+    lapack_order = ['mkl', 'openblas', 'flame', 'atlas', 'lapack']
     order_env_var_name = 'NPY_LAPACK_ORDER'
 
     def _calc_info_mkl(self):
@@ -1823,7 +1841,7 @@ class lapack64__opt_info(lapack_ilp64_opt_info):
 class blas_opt_info(system_info):
     notfounderror = BlasNotFoundError
     # List of all known BLAS libraries, in the default order
-    blas_order = ['mkl', 'blis', 'openblas', 'atlas', 'accelerate', 'blas']
+    blas_order = ['mkl', 'blis', 'openblas', 'atlas', 'blas']
     order_env_var_name = 'NPY_BLAS_ORDER'
 
     def _calc_info_mkl(self):