diff --git a/.travis.yml b/.travis.yml
index 3797ddf..dbf5d19 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -84,6 +84,22 @@ matrix:
           sources:
             - ubuntu-toolchain-r-test
 
+    - os: linux
+      compiler: clang++
+      env: TOOLSET=clang COMPILER=clang++ CXXSTD=11
+      addons:
+        apt:
+          packages:
+            - clang-3.3
+
+    - os: linux
+      compiler: clang++
+      env: TOOLSET=clang COMPILER=clang++ CXXSTD=11
+      addons:
+        apt:
+          packages:
+            - clang-3.4
+
     - os: linux
       compiler: clang++-3.5
       env: TOOLSET=clang COMPILER=clang++-3.5 CXXSTD=11,14,1z