diff --git a/scripts/utils.sh b/scripts/utils.sh
index 0d120473bb63b168a37b0e144637192d0a89006c..c71de666ac65f491e2d314b43071506d4fe4c74d 100644
--- a/scripts/utils.sh
+++ b/scripts/utils.sh
@@ -132,9 +132,9 @@ function fail_on_warnings() {
   then
     echoerr "There were warnings:"
     echoerr "======================== Filtered warnings ====================================="
-    echo "$warnings"
+    echo "$warnings" >&2
     echoerr "======================= Unfiltered warnings ===================================="
-    cat "$warning_file"
+    cat "$warning_file" >&2
     echoerr "================================================================================"
     rm -f "$warning_file"
     return 1