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From: "ldionne.2 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/110000] GCC should implement
 exclude_from_explicit_instantiation
Date: Wed, 31 May 2023 15:40:05 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110000

--- Comment #9 from Louis Dionne <ldionne.2 at gmail dot com> ---
(In reply to Andrew Pinski from comment #3)
> I am getting a feeling this attribute is well defined enough.
>=20
> Is it really just supposed to block explicit instantiation of templates?
> Is there a decent set of testcases that can be used to match up the
> implementations here? Because I suspect without those it will be implemen=
ted
> slightly different.

Is there anything specific you're thinking about that would be insufficient=
ly
defined? It's possible that that's the case, and if so then we can define it
properly and make sure Clang/GCC are aligned on the semantics.

This is quite a painful issue for libc++ on GCC since the current solution =
is
to use `always_inline`, which has too many downsides. It used to be just an
annoyance, but with the addition of libraries like `std::format`, using
`always_inline` leads to a library that is literally unusable in some cases
(compile times and code size just skyrockets). So yeah, we're much willing =
to
collaborate in order to make this work.=