[pcwalton]

Generally, Rust "should" be faster, because it spends a lot of time on optimizations that Go doesn't do. That's what you're paying for in compile times. If Go is faster on some CPU bound workload despite doing a lot less optimization, that's interesting. (I should note that this is not the norm.)

[rlonn]

Or, written another way: In theory, practise is like theory. In practise, it isn't :)

[constexpr]

I'm not sure that this is a CPU bound workload. You're right that if this is CPU bound, LLVM's code generation should come out on top, even if only slightly, but that's not the case. Perhaps writing a JavaScript bundler is more of a memory bound or I/O bound task than a CPU bound task?

[no_wizard]

What optimizations is Go not doing that Rust is that makes Rust vastly superior to Go? (Or even superior at all)

I don’t think it’s that simple. I understand Go uses garbage collection but that doesn’t automatically mean Go doesn’t do compile time optimizations or is poor at CPU bound work.

While I understand GCs add overhead I don’t think that in and of itself means much here

This seems like yak shaving to me