diff --git a/.travis.yml b/.travis.yml
index d27e93f7..f4e0ea04 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -148,6 +148,7 @@ matrix:
         apt:
           packages:
             - clang-4.0
+            - libstdc++-4.9-dev
           sources:
             - ubuntu-toolchain-r-test
             - llvm-toolchain-trusty-4.0