travis: remove duplicate xcode image and add comments

We already build on whatever the default Travis xcode image is
which is currently 9.4 so remove the duplicate build targeting 9.4 and
add some comments explaining the purpose of the different builds.

Signed-off-by: Sitsofe Wheeler <sitsofe@yahoo.com>

diff --git a/.travis.yml b/.travis.yml
index eee319880028060df5cb71a122dbeb2ffe47d658..b34264e34fcd417c4e2cc5e0c99950e527a3da38 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,13 +12,11 @@ env:
     - MAKEFLAGS="-j 2"
 matrix:
   include:
+    # Default xcode image
     - os: osx
       compiler: clang # Workaround travis setting CC=["clang", "gcc"]
       env: BUILD_ARCH="x86_64"
-    - os: osx
-      compiler: clang
-      osx_image: xcode9.4
-      env: BUILD_ARCH="x86_64"
+    # Latest xcode image (needs periodic updating)
     - os: osx
       compiler: clang
       osx_image: xcode11.2