How to test using a variety of build options with AWS CodeBuild

I am using AWS CodeBuild as a replacement for travis-ci.org. (Travis-CI was just too slow for our needs.) I would like to have CodeBuild test a variety of different configurations:

• static vs shared libraries
• gnu vs llvm compilers
• debug vs release optimizations

I have a very simple buildspec.yml file that works well, but it doesn't seem to be able to generate a matrix of options like I can do on Travis-CI.

I could create a variety of buildspec.yml files with each one doing something a little differently, but that quickly gets out of hand with the different options that need to be considered.

What is the right/best way to do this with AWS CodeBuild?