diff --git a/utils/tests/gitlab-ci.yml b/utils/tests/gitlab-ci.yml
index fa687f218..e8b011970 100644
--- a/utils/tests/gitlab-ci.yml
+++ b/utils/tests/gitlab-ci.yml
@@ -43,7 +43,7 @@ workflow:
     - export CCACHE_BASEDIR=${PWD}
     - export CCACHE_DIR=${PWD}/$CCACHE_BASEDIR_VALUE
     - export MPI_CI=1
-    - CXX=$COMPILER ./ns3 configure -d $MODE -GNinja --enable-examples --enable-tests --enable-asserts $ENABLE_MPI
+    - CXX=$COMPILER ./ns3 configure -d $MODE -GNinja --enable-examples --enable-tests --enable-asserts --enable-werror $ENABLE_MPI
       $EXTRA_OPTIONS
     - ccache -z
     - if [[ "$CI_JOB_STAGE" == "build" ]];