diff --git a/scripts/cov.sh b/scripts/cov.sh
index 13d042905..2c9ad09f5 100755
--- a/scripts/cov.sh
+++ b/scripts/cov.sh
@@ -21,7 +21,7 @@ if ! type $KCOV > /dev/null; then
 fi
 
 . ./scripts/targets.sh
-cargo test $TARGETS --no-run || exit $?
+RUSTFLAGS="-C link-dead-code" cargo test $TARGETS --no-run || exit $?
 
 
 KCOV_TARGET="target/cov"
@@ -46,10 +46,10 @@ mkdir -p $KCOV_TARGET
 echo "Cover RUST"
 for FILE in `find target/debug/deps ! -name "*.*"`
 do
-	$KCOV --exclude-pattern $EXCLUDE $KCOV_FLAGS $KCOV_TARGET $FILE
+	$KCOV --exclude-pattern $EXCLUDE $KCOV_FLAGS $KCOV_TARGET $FILE --verify
 done
 
-$KCOV --exclude-pattern $EXCLUDE $KCOV_FLAGS $KCOV_TARGET target/debug/parity-*
+$KCOV --exclude-pattern $EXCLUDE $KCOV_FLAGS $KCOV_TARGET target/debug/parity-* --verify
 echo "Cover JS"
 cd js
 npm install&&npm run test:coverage