diff --git a/.github/workflows/auto-build.yml b/.github/workflows/auto-build.yml
index bcf0ed6..c2afb05 100644
--- a/.github/workflows/auto-build.yml
+++ b/.github/workflows/auto-build.yml
@@ -23,6 +23,8 @@ jobs:
 
       - name: Checkout repository
         uses: actions/checkout@v2
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
 
       - name: Auto build
         run: make build