DMD (the D compiler) has long been source-available, but non-Free. However, it was just now re-licensed to be entirely Free. This includes existing releases; we don't need to wait for a new release with the new license to come out.

https://forum.dlang.org/thread/oc8acc$1ei9$1@digitalmars.com#post-oc8acc:241ei9:241:40digitalmars.com

In addition to DMD itself, there are several packages that are blacklisted for requiring DMD.