diff --git a/Tools/scripts/build_ci.sh b/Tools/scripts/build_ci.sh
index 61c01a66cbe9fa..da7e569c6232e3 100755
--- a/Tools/scripts/build_ci.sh
+++ b/Tools/scripts/build_ci.sh
@@ -10,7 +10,6 @@ set -ex
 # CXX and CC are exported by default by travis
 c_compiler=${CC:-gcc}
 cxx_compiler=${CXX:-g++}
-unset CXX CC
 
 export BUILDROOT=/tmp/ci.build
 rm -rf $BUILDROOT