Visual C++ to my knowledge does not support incremental or parallel compilation within the compile unit. It does support incremental linking though, and parallel compilation of multiple compile units that don't depend on each other. Features which both clang and rustc have btw (well clang only concerns one compile unit, so the parallelism depends on how you call clang, but many clang calling build systems support parallelism).

No idea about C++ Builder. Do you have links to documentation to back it up? I'm curious :).

You didn't mentioned it was within the same compile unit, just parallel code generation.

In any case, have a look here,

https://docs.microsoft.com/en-us/cpp/build/reference/cgthrea...

Most C++ compilers support precompiled headers, which would be the closest equivalent to incremental compilation within a single compilation unit.