diff --git a/.github/workflows/nightly-build.yml b/.github/workflows/nightly-build.yml
index 48ef497..f0d94f3 100644
--- a/.github/workflows/nightly-build.yml
+++ b/.github/workflows/nightly-build.yml
@@ -56,12 +56,14 @@ jobs:
       shell: bash
       if: runner.os == 'macOS'
       run: |
-        brew info --cask gfortran
-        brew install --cask gfortran
-        ls -l /usr/local/gfortran/bin/
-        sudo ln -fs /usr/local/gfortran/bin/gfortran /usr/local/bin/gfortran
-        sudo ln -fs /usr/local/gfortran/bin/gcc /usr/local/bin/gcc
-        sudo ln -fs /usr/local/gfortran/bin/g++ /usr/local/bin/g++
+        if ! command -v gfortran &> /dev/null
+        then
+            brew info --cask gfortran
+            brew install --cask gfortran
+            ls -l /usr/local/gfortran/bin/
+            sudo ln -fs /usr/local/gfortran/bin/gfortran /usr/local/bin/gfortran
+            sudo ln -fs /usr/local/gfortran/bin/gcc /usr/local/bin/gcc
+            sudo ln -fs /usr/local/gfortran/bin/g++ /usr/local/bin/g++
 
     - name: Print GNU compiler versions
       shell: bash