rvalues -> ref (yup... again!)

[kinke]

On Tuesday, 27 March 2018 at 21:52:25 UTC, Rubn wrote:
> It happens with LDC too, not sure how it would be able to know 
> to do any kind of optimization like that unless it was able to 
> inline every single function called into one function and be 
> able to do optimize it from there. I don't imagine that'll be 
> likely though.

It does it in your code sample with `-O`, there's no call to bar 
and the foo() by-value arg is memcpy'd to the global.

If you compile everything with LTO, your code and all 3rd-party 
libs as well as druntime/Phobos, LLVM is able to optimize the 
whole program as if it were inside a single gigantic 'object' 
file in LLVM bitcode IR, and is thus indeed theoretically able to 
inline *all* functions.