Hi Folks > On 11 Aug 2021, at 11:55, Segher Boessenkool <seg...@kernel.crashing.org> > wrote:
> On Tue, Aug 10, 2021 at 04:46:11PM -0600, Sandra Loosemore wrote: >> OK. I used your wording verbatim for the first one. For the second >> one, I'm still pretty confused as I think it is at least theoretically >> possible on PowerPC to have a target with 64-bit long double (AIX?) that > > Some embedded and embedded-like subtargets use 64-bit long double by > default. You can also configure this on any Power target (not that it > will necessarily work ;-) ) > > I don't know if any subtarget with default 64-bit long double supports > Fortran. I realize that this is not directly relevant to unscrambling the PPC 128bit stuff, but aarch64-apple-darwin2x has only 64b long double and supports gfortran. (on both the new M1 desktop macOS and embedded iOS) - it is not clear to me yet if there will at some point be a transition to a 128b long double for at least the desktop version. So the permutation definitely exists for at least one non-legacy, non-embedded platform (and gfortran is very much in demand from the new M1 users). Iain >> also supports the __ibm128 format, and it would be wrong to assume that >> *any* 128-bit mode that's not long double is IEEE. > > Absolutely. Modes are not types, and types are not modes. There are > 128-bit floating point modes that are not IEEE, there are that are, and > either can be used for long double, or neither. > > > Segher
