diff --git a/functions-common b/functions-common
index 9e4b31c1f2..228cb2aa62 100644
--- a/functions-common
+++ b/functions-common
@@ -1225,14 +1225,12 @@ function pip_install {
 function setup_develop {
     local project_dir=$1
 
-    echo "cd $REQUIREMENTS_DIR; $SUDO_CMD python update.py $project_dir"
-
     # Don't update repo if local changes exist
     # Don't use buggy "git diff --quiet"
-    (cd $project_dir && git diff --exit-code >/dev/null)
-    local update_requirements=$?
+    # ``errexit`` requires us to trap the exit code when the repo is changed
+    local update_requirements=$(cd $project_dir && git diff --exit-code >/dev/null || echo "changed")
 
-    if [ $update_requirements -eq 0 ]; then
+    if [[ $update_requirements = "changed" ]]; then
         (cd $REQUIREMENTS_DIR; \
             $SUDO_CMD python update.py $project_dir)
     fi
@@ -1248,7 +1246,7 @@ function setup_develop {
     # a variable that tells us whether or not we should UNDO the requirements
     # changes (this will be set to False in the OpenStack ci gate)
     if [ $UNDO_REQUIREMENTS = "True" ]; then
-        if [ $update_requirements -eq 0 ]; then
+        if [[ $update_requirements = "changed" ]]; then
             (cd $project_dir && git reset --hard)
         fi
     fi