- stop pruning optimizations coming from the environment (ie OpenBSD's default -O2 -pipe) when building llvm - this resulted in a very slow llvm, and in a veeery slow rust build, and an awfully slow rust compiler. Yay. See https://github.com/rust-lang/rust/issues/39900 - only add cmake to BDEP when rustc is compiled with bundled llvm - propagate verbose cmake flag to bundled llvm build tested on i386 and amd64