diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index ce7fd3d3dd39a750be20e6f20559ee09c734c057..5bd1c4d571b16702318c6dbba5e39f9c89dc6664 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -36,7 +36,7 @@ build-img:
             -DCMAKE_MODULE_PATH=$PWD/build
             -DCMAKE_BUILD_TYPE=Debug
             -DCSG_CGAL_ENABLED=${ENABLE_CGAL}
-            -DCMAKE_CXX_FLAGS="-pedantic"
+            -DCMAKE_CXX_FLAGS="-pedantic-errors"
     - cmake --build build --target unit_tests_csg
     - cd build
     - ctest