kc3-lang/libffi

diff --git a/.travis/install.sh b/.travis/install.sh
index d9dd31a..66f81f8 100755
--- a/.travis/install.sh
+++ b/.travis/install.sh
@@ -1,4 +1,5 @@
 #!/bin/bash
+set -x
 
 if [[ $TRAVIS_OS_NAME != 'linux' ]]; then
   brew update