diff --git a/ci/test-stable-perf.sh b/ci/test-stable-perf.sh
index 572fd3e963..55c039ff0d 100755
--- a/ci/test-stable-perf.sh
+++ b/ci/test-stable-perf.sh
@@ -9,6 +9,7 @@ if ! ci/version-check.sh stable; then
   ci/version-check.sh stable
 fi
 export RUST_BACKTRACE=1
+export RUSTFLAGS="-D warnings"
 
 ./fetch-perf-libs.sh
 export LD_LIBRARY_PATH=$PWD/target/perf-libs:/usr/local/cuda/lib64:$LD_LIBRARY_PATH
diff --git a/ci/test-stable.sh b/ci/test-stable.sh
index 1ad7998c9e..e2797dd91c 100755
--- a/ci/test-stable.sh
+++ b/ci/test-stable.sh
@@ -4,6 +4,7 @@ cd "$(dirname "$0")/.."
 
 ci/version-check.sh stable
 export RUST_BACKTRACE=1
+export RUSTFLAGS="-D warnings"
 
 _() {
   echo "--- $*"