On Mon, 08 Feb 2021, Florian Weimer wrote:
The OpenPOWER 64-Bit ELF V2 ABI Specification makes VSX support
non-optional, as far as I can tell. If it does not, that would be a bug
in the document because it's definitely the intent.
is what you are referring to, right? Could you give me a pointer where this
specification makes VSX support non-optional?
It is possible to define a different ABI without VSX support, but it
would have a different GNU triplet (not powerpc64le-*-linux-gnu) and a
different RPM architecture (not ppc64le).
And why can't VSX support be optional, because introducing another GNU
triplet and a different RPM architecture (and same for DEB etc.) seems to
be much work. My comparison might be wrong, but for e.g. x86_64 lots of
CPU features are optional, and we just have one x86_64 RPM architecture.
The question is not about "because the specification says so", but about
the technical reason why it can't be made optional (as you figured out, I
am not an expert here, but I would like to actually understand it).