PKG: Suppress error for double initialisation of OpenMP

Author: RUrlus

src/sparse_dot_topn/__init__.py

@@ -1,5 +1,24 @@
 # Copyright (c) 2023 ING Analytics Wholesale Banking
 import importlib.metadata
+import os
+
+# Setting the following environment variable allows multiple OpenMP
+# libraries to be loaded. This is also used without issue by Scikit-learn.
+# OpenMP error msg:
+# /* OMP: Error #15: Initializing libomp.dylib, but found libomp.dylib already initialized.
+#  * OMP: Hint This means that multiple copies of the OpenMP runtime have been linked into the program.
+#  * That is dangerous, since it can degrade performance or cause incorrect results.
+#  * The best thing to do is to ensure that only a single OpenMP runtime is linked into the process,
+#  * e.g. by avoiding static linking of the OpenMP runtime in any library.
+#  * As an unsafe, unsupported, undocumented workaround you can set the environment variable KMP_DUPLICATE_LIB_OK=TRUE
+#  * to allow the program to continue to execute, but that may cause crashes or silently produce incorrect results.
+#  * For more information, please see http://openmp.llvm.org/
+#  */
+os.environ.setdefault("KMP_DUPLICATE_LIB_OK", "True")
+
+# Workaround issue discovered in intel-openmp 2019.5:
+# https://github.com/ContinuumIO/anaconda-issues/issues/11294
+os.environ.setdefault("KMP_INIT_AT_FORK", "FALSE")
 
 __version__ = importlib.metadata.version("sparse_dot_topn")
 from sparse_dot_topn.api import awesome_cossim_topn, sp_matmul, sp_matmul_topn, zip_sp_matmul_topn