diff --git a/.github/workflows/test-build.yml b/.github/workflows/test-build.yml
index c80086f..9d701ff 100644
--- a/.github/workflows/test-build.yml
+++ b/.github/workflows/test-build.yml
@@ -33,7 +33,7 @@ jobs:
     - uses: actions/checkout@v2
     - name: install dependencies
       run: |
-        brew install gcc@9
+        brew install --cask gfortran
         brew install emacs
         brew install autoconf automake libtool
     - name: Run test