find gcc only under /usr/local/bin

.github/workflows/python-publish.yml

@@ -34,6 +34,12 @@ jobs:
     - name: Display Python version
       run: python -c "import sys; print(sys.version)"
     
+    - name: Install GCC for MacOS using Homebrew
+      if: matrix.os == 'macos-latest'
+      run: |
+        brew install gcc libomp llvm
+        brew link gcc
+    
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip

setup.py

@@ -43,8 +43,6 @@ USE_OPENMP = True
 def extract_gcc_binaries():
     """Try to find GCC on OSX for OpenMP support."""
     patterns = [
-        "/opt/local/bin/g++-mp-[0-9].[0-9]",
-        "/opt/local/bin/g++-mp-[0-9]",
         "/usr/local/bin/g++-[0-9].[0-9]",
         "/usr/local/bin/g++-[0-9]",
     ]
@@ -83,11 +81,11 @@ else:
     ]
 
     if "darwin" in platform.platform().lower():
-        USE_OPENMP = False  # temporarily disable for GH actions 
         if gcc is not None:
             os.environ["CC"] = gcc
             os.environ["CXX"] = gcc
         else:
+            USE_OPENMP = False
             print(
                 "No GCC available. Install gcc from Homebrew " "using brew install gcc."
             )