diff --git a/irr/.github/workflows/build.yml b/irr/.github/workflows/build.yml
index b6d32d76c..5a11bca2a 100644
--- a/irr/.github/workflows/build.yml
+++ b/irr/.github/workflows/build.yml
@@ -153,7 +153,7 @@ jobs:
         run: |
           mkdir build
           cd build
-          cmake -G Ninja -DCMAKE_CXX_COMPILER=/usr/bin/g++-5 -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_FLAGS="-Werror" ..
+          cmake -G Ninja -DCMAKE_C_COMPILER=/usr/bin/g++-5 -DCMAKE_CXX_COMPILER=/usr/bin/g++-5 -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_FLAGS="-Werror" ..
           cmake --build .
           cd ..