diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index a38bbda9..92bb8078 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -833,7 +833,7 @@ jobs:
         run: |
           GAM_RUN_COUNT=0
           run_gam() {
-            ((GAM_RUN_COUNT++))
+            GAM_RUN_COUNT=$((GAM_RUN_COUNT + 1))
             local allowed_codes="0"
             if [[ "$1" == "-a" ]]; then
               allowed_codes="$2"