And, fairly uniquely, LLVM has a LLVM_PARALLEL_LINK_JOBS setting that is distinct from the number of parallel jobs for everything else. I think I was using that 15 years ago.

I wish GCC had it. I have a quad core machine with 16 GB RAM that OOMs on building recent GCC -- 15 and HEAD for sure, can't remember whether 14 is affected. Enabling even 1 GB of swap makes it work. The culprit is four parallel link jobs needing ~4 GB each.

There are only four of them, so a -j8 build (e.g., with HT) is no worse.