diff --git a/.travis.yml b/.travis.yml
index 0c849c39e..e3595ff37 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -20,6 +20,11 @@ cache:
   directories:
   - $HOME/.ccache
 
+     - ubuntu-toolchain-r-test
+     - llvm-toolchain-precise-3.5
+    packages:
+     - clang-3.5
+
 matrix:
   include:
     - os: linux
@@ -28,8 +33,8 @@ matrix:
       env: JOBS=8 MASON_PUBLISH=true CXX="ccache clang++-3.8 -Qunused-arguments" CC="clang-3.8" TRIGGER=true
       addons:
         apt:
-          sources: [ 'ubuntu-toolchain-r-test']
-          packages: [ 'libstdc++-4.9-dev', 'xutils-dev']
+          sources: [ 'ubuntu-toolchain-r-test', 'llvm-toolchain-precise-3.5']
+          packages: [ 'clang-3.5']
           # libstdc++-4.9-dev,libstdc++6 4.9.3-13ubuntu2
           # libstdc++-5-dev,libstdc++6 5.4.0-6ubuntu1~16.04.2
     - os: linux
@@ -38,8 +43,8 @@ matrix:
       env: JOBS=8 COVERAGE=true CXX="ccache clang++-3.8 -Qunused-arguments" CC="clang-3.8"
       addons:
         apt:
-          sources: [ 'ubuntu-toolchain-r-test']
-          packages: [ 'libstdc++-4.9-dev', 'xutils-dev' ]
+          sources: [ 'ubuntu-toolchain-r-test', 'llvm-toolchain-precise-3.5']
+          packages: [ 'clang-3.5']
     - os: osx
       compiler: ": clang-osx"
       # https://docs.travis-ci.com/user/languages/objective-c/#Supported-OS-X-iOS-SDK-versions