[cxx-abi-dev] Passing non-trivial types through ...

[Jason Merrill]

In C++11 this is conditionally-supported with implementation-defined 
behavior.  G++ has disallowed this via either runtime abort or error 
since GCC 3.2, but a customer recently asked us to allow it, and it 
occurs to me that the obvious way around the problems with bitwise 
copying is to implement this as pass-by-invisible-reference, just like 
normal value argument passing.  Any objections?

Jason