Re: C++20 and gcc12/10

[Havard Eidnes <he%NetBSD.org@localhost>]

> No, this belongs in infrastructure.  A package should only have to
> declare what it needs in terms of compiler support, not have
> OS-specific hacks spread across them.  Since adding support for
> *_FEATURES there shouldn't be any GCC_REQD in packages.

Well.

What to do when "older" GCCs do not produce a working result?
Such as e.g. gcc < 12 fails to build a working LLVM 18.x as part
of the rust package on sparc64?  That's sort of hard to express
using the *_FEATURES settings.

Same goes for our 32-bit powerpc ports needing GCC >= 14 to build
without falling over with

assertion "memcmp(mf_ptr(mf) - 1, mf_ptr(mf) - matches[i].dist - 2, matches[i].len) == 0" failed: file "xz-5.2/src/liblzma/lz/lz_encoder_mf.c", line 40, function "lzma_mf_find"

(tested and failed both with in-tree gcc10 and pkgsrc gcc12 on
NetBSD/macppc 10.0)

Regards,

- Håvard