👷 trying new Travis workers

.travis.yml

@@ -128,9 +128,6 @@ matrix:
 
   # OSX / Clang
 
-  - os: osx
-    osx_image: xcode6.4
-
   - os: osx
     osx_image: xcode7.3
 
@@ -164,6 +161,9 @@ matrix:
   - os: osx
     osx_image: xcode10
 
+  - os: osx
+    osx_image: xcode10.1
+
   # Linux / GCC
 
   - os: linux
@@ -290,6 +290,14 @@ matrix:
         sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-trusty-6.0']
         packages: ['g++-6', 'clang-6.0', 'ninja-build']
 
+  - os: linux
+    compiler: clang
+    env: COMPILER=clang++-7.0
+    addons:
+      apt:
+        sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-trusty-7']
+        packages: ['g++-6', 'clang-7.0', 'ninja-build']
+
   - os: linux
     compiler: clang
     env: