Use fresh OSX image
diff --git a/.travis.yml b/.travis.yml
index b57e9ef..2d4827d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -154,16 +154,20 @@
## We'll just test 4.4 and the most recent version.
###
- os: osx
+ osx_image: xcode12.2
env: BUILD_SYSTEM=cmake C_COMPILER=gcc CXX_COMPILER=g++
- os: osx
+ osx_image: xcode12.2
env: BUILD_SYSTEM=cmake C_COMPILER=gcc-4.9 CXX_COMPILER=g++-4.9
- os: osx
+ osx_image: xcode12.2
env: BUILD_SYSTEM=cmake
###
## Python 2.7 OS X build (using the system /usr/bin/python)
###
- os: osx
+ osx_image: xcode12.2
env: BUILD_SYSTEM=python C_COMPILER=gcc CXX_COMPILER=g++
###
@@ -219,8 +223,8 @@
- bazel
- os: osx
+ osx_image: xcode12.2
env: BUILD_SYSTEM=bazel
- osx_image: xcode11.3
language: java
before_install: