[OE-core] pseudo: host user contamination

[Seebs]

On Thu, 29 Mar 2018 14:04:00 +0200
Enrico Scholz <enrico.scholz at sigma-chemnitz.de> wrote:
> __builtin_apply() should deal with it.

The documentation hints at possible problems when dealing with other
functions, but doesn't mention any architecture difficulties. It's
possible gcc simply never uses any of the weird conventions, it's also
possible that builtin_apply just doesn't work reliably on such
architectures. The gcc docs do state that gcc's calling conventions
never depend on whether a function has a fixed or variadic argument
list, which suggests that it's probably safe-ish. (Some compilers use
very different calling conventions for variadic functions.)

-s