diff --git a/.travis.yml b/.travis.yml
index 5b38f3bc..e1cc617f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -88,6 +88,15 @@ matrix:
           sources:
             - ubuntu-toolchain-r-test
 
+    - os: linux
+      env: TOOLSET=gcc COMPILER=g++-5 CXXSTD=03,11,14,1z CXXSTD_DIALECT=cxxstd-dialect=gnu
+      addons:
+        apt:
+          packages:
+            - g++-5
+          sources:
+            - ubuntu-toolchain-r-test
+
     - os: linux
       env: TOOLSET=gcc COMPILER=g++-6 CXXSTD=03,11,14,1z
       addons: