Re: Can the return value of a proc be a variable marked {.global.} ?

[cblake]

@Kaushalmodi's issue, while interesting, is fairly independent since it almost 
certainly is just about `gcc` and not, say, `clang` (and quite probably just 
some range of versions of `gcc`). And people can fiddle with their `-O` levels 
in `gcc.options.speed` in `nim.cfg/etc`. I don't think it really argues/advises 
against @mratsim's warning/hint solution.