I appreciate the detailed replies! I guess complex is an ambiguous word. Let's just agree that template-heavy "modern" C++ needs more optimizations turned on t

I appreciate the detailed replies! I guess complex is an ambiguous word. Let's just agree that template-heavy "modern" C++ needs more optimizations turned on to get decent performance. So more optimizations => longer compiler times. (Not to even mention all of the parsing the headers multiple times, plus generating multiple versions of the code for all of the various type specializations!) From the other replies, I feel like there's more to it than just optimizations though -- but as just a compiler-user, not a compiler-writer, I'm out of my depth and just reading tea leaves. :) Reading those tea leaves, I'll be sadly surprised if the Go compiler ends up slow and happily surprised if a C++ compiler ever ends up as fast. (I don't know enough about Rust to make any predictions. ;) (PS. No disagreement that C++ has a higher performance ceiling than Go; of course hand-rolled asm still goes higher than that (ever tried running x264 w/o the assembly bits? it's painfully slow).)