[petters]

Compiling C++ is usually pretty slow. Go and C would be significantly faster.

[Twirrim]

One of the focuses with Go's compilation design was trying to avoid all the extra work that happens in C compilation that could be avoided by some careful language design.

There's a good write up here: https://talks.golang.org/2012/splash.article, but particularly starting at point 5 on that page.