Update buildbinaryen.yml.

Author: Tweety-Lab

.github/workflows/buildbinaryen.yml

@@ -44,9 +44,17 @@ jobs:
 
       - name: Configure
         run: cmake -S binaryen -B binaryen/build ${{ matrix.cmake-args }}
-
+        
       - name: Build
-        run: cmake --build binaryen/build -- -j$(nproc || sysctl -n hw.ncpu)
+        run: |
+          if [ "${{ runner.os }}" = "Linux" ]; then
+            cmake --build binaryen/build -- -j$(nproc)
+          elif [ "${{ runner.os }}" = "macOS" ]; then
+            cmake --build binaryen/build -- -j$(sysctl -n hw.ncpu)
+          else
+            cmake --build binaryen/build -- -j
+          fi
+        shell: bash
 
       - name: Copy to NuGet runtime folder
         run: |