diff --git a/CI/before_install.osx.sh b/CI/before_install.osx.sh
index 9adf4dfa5e..49b2fbe167 100755
--- a/CI/before_install.osx.sh
+++ b/CI/before_install.osx.sh
@@ -1,4 +1,4 @@
-#!/bin/sh -e
+#!/bin/sh -ex
 
 # workaround python issue on travis
 HOMEBREW_NO_AUTO_UPDATE=1 brew uninstall --ignore-dependencies python@3.8 || true