Appveyor builds are not working. The build scripts use chocolatey to install some tools like winflexbison for MSVC builds, and that chocolatey package is currently broken. The maintainer has been notified. I haven't found a good workaround yet.
Travis CI builds should be more stable, but I am seeing some issues in the builds on Github. As part of merging in Common Lisp language support I am planning to switch the baseline build (including all cross tests) to Ubuntu Artful (17.10) which has a sbcl implementation in it. We will continue to build one build job on trusty and xenial (autotools.sh, which runs "make check"). I am working on these issues. - Jim
