Re: [PATCH], Add weak references to bridge old/new PowerPC ieee 128-bit name mangling

[Jakub Jelinek <jakub at redhat dot com>]

On Tue, Jun 05, 2018 at 04:08:13PM +0000, Joseph Myers wrote:
> On Tue, 5 Jun 2018, Jakub Jelinek wrote:
> 
> > If we need the C separate _FloatNN types in C++, they can mangle the way we
> > (and others) agree on.  Would _Float64 be distinct from double and thus
> > mangle differently from "d"?
> 
> Right now it (as accessed via __typeof on built-in functions since the 
> _FloatN keywords and constant suffixes don't exist in C++) is different 
> and results in an ICE (bug 85518).  Either it needs to be the same as 
> double for C++ (on all architectures, and similarly for _Float32x and all 
> the other _FloatN / _FloatNx types with the same format as a standard 
> type; and similarly for the _Float64x, _Float128 pair when both are 
> distinct from long double, and currently both are distinct from each other 
> as well), or else appropriate mangling, presumably DF<number>_, is needed 
> for those types (and the ABI would need extending upstream to cover the 
> _FloatNx types as well in that case).

Or guard the builtins on C/ObjC and not C++/ObjC++, e.g. by tweaking
DEF_FLOATN_BUILTIN define somehow.

	Jakub