No. I'm claiming it doesn't perform anywhere near the level of optimization of GCC and LLVM.
> I'd think Java can certainly be considered having highly optimized compiler / runtime. But it has almost same performance as Go and much higher memory usage compared to Go.
I disagree with what seems to be your implication that compiler optimizations don't matter (and almost everyone else who works on compilers would also disagree), but I don't really want to turn this thread into a critique of the benchmarks game, so let's just leave it at that.
Please don't jump to the conclusion that huge differences in the default memory allocation of tiny 100 line programs means there will be similar huge differences between ordinary large programs.
Notice that even for those tiny 100 line programs, the difference can be more like 2x when memory actually needs to allocated for the task.
† Which can be seen as a runtime cost for interpreter+JIT languages, but that's a different issue. We're talking time-to-steady-state when the interpreter is fed a file (which is something Javascript engine devs worry about a lot), not benchmark-speed-at-steady-state.
http://benchmarksgame.alioth.debian.org/u64q/go.html