diff --git a/.github/workflows/autotools.yml b/.github/workflows/autotools.yml
index 9299a4b77..b890f7ae2 100644
--- a/.github/workflows/autotools.yml
+++ b/.github/workflows/autotools.yml
@@ -23,4 +23,18 @@ jobs:
       run: |
         for i in `find . -name configure`; do sed -i 's/From configure.ac .*//' $i; done
     - name: Check diff
-      run: git diff | tee .gitdiff && cat .gitdiff && if [ -s .gitdiff ]; then exit 1; fi
+      run: |
+        git diff | tee .gitdiff
+        if [ "${{ github.event_name }}" = "pull_request" ]; then
+          if [ -s .gitdiff ]; then
+            gh pr edit "${{ github.event.number }}" --add-label "misc/runautotools"
+          else
+            gh pr edit "${{ github.event.number }}" --remove-label "misc/runautotools"
+          fi
+        else
+          if [ -s .gitdiff ]; then
+            exit 1
+          fi
+        fi
+      env:
+        NUMBER: {% raw %}${{ github.event.number }}{% endraw %}