I'd like to remove the ancient llvm and clang 3.5 ports, but the current gnome-builder depends on them. Newer version of gnome-builder seem to support at least somewhat never llvm versions, but the documentation is a bit thin. I've not tried doing an update as the build system has changed to CMake so the port will need some changes.
(In reply to Brooks Davis from comment #0) Also see https://wiki.freebsd.org/ObsoleteLLVMVersions .
This problem will be resolved then the GNOME 3.28 update lands.
GNOME Builder doesn't really depend on a specific LLVM version, and the reason that both GNOME Builder and Meson have a hard-coded list of LLVM versions are that FreeBSD doesn't have an unversioned 'llvm-config' executable. I have sent patches to GNOME Builder upstream several times to expand the list, and all are done without any code changes.
Right now it actually depends upon clang35: ./build/autotools/autoconf.d/pre-am.m4:m4_define(clang_major_required_version, 3) ./build/autotools/autoconf.d/pre-am.m4:m4_define(clang_minor_required_version, 5) and it looks like it's easy to change these two values to test. But my gnome environment and gnome-builder itself are from gnome 3.26, so I can't test this 3.16 version reliable to change the clang/llvm dependency.
It was switched to devel/llvm60 in r480951