Try update-alternatives ld

Author: phadej

.travis.yml

@@ -103,6 +103,9 @@ before_install:
  - export PATH=/opt/cabal/1.24/bin:$PATH
  - export PATH=/opt/happy/1.19.5/bin:$PATH
  - export PATH=/opt/alex/3.1.7/bin:$PATH
+ - if [ "$TRAVIS_OS_NAME" = "linux" ]; then sudo update-alternatives --install "/usr/bin/ld" "ld" "/usr/bin/ld.gold" 20; fi
+ - if [ "$TRAVIS_OS_NAME" = "linux" ]; then sudo update-alternatives --install "/usr/bin/ld" "ld" "/usr/bin/ld.bfd" 10; fi
+ - ld --version
  - ./travis-install.sh
 
 install: