Fil-C seems interesting, and I didn’t understand the details of how multi-threaded garbage collectors worked before reading it (I still don’t but I’m closer!). The tradeoff between a compacting garbage collector (Java) vs what you can bolt on to C without forking LLVM is particularly interesting.
Note that it is very simplistic to say Java has a compacting garbage collector, between Oracle JDK, OpenJDK, Temurin, Azul, PTC, Aicas, microEJ, OpenJ9, GraalVM, Jikes RVM, and the cousin Android, there is pleothora of GC configurations to chose from, that go beyond that.
Not to mention that many of them have multiple GC's that are selected as startup options.
Personally though I can't wait for Azul's patents to start running out so that OS vendors can start implementing similar machinery into mainline OS's for all runtimes to use.
