travis: use ruby 2.6.4 because of swig incompatibility
@@ -212,8 +212,8 @@ matrix:
before_install:
- |
if [ "$TRAVIS_OS_NAME" = 'osx' ]; then
- rvm install 2.7.0
- rvm use 2.7.0
+ rvm install 2.6.4
+ rvm use 2.6.4
gem install test-unit --no-document
if [ "$CC" = 'gcc' ]; then
brew upgrade gcc@9
