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Date: Wed, 14 Jun 2023 14:52:46 +0000
From: Joseph Myers <joseph@codesourcery.com>
To: Paul Eggert <eggert@cs.ucla.edu>
CC: Jakub Jelinek <jakub@redhat.com>, Marek Polacek <polacek@redhat.com>,
	<gcc-patches@gcc.gnu.org>, <libc-alpha@sourceware.org>
Subject: Re: [RFC] Add stdckdint.h header for C23
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On Tue, 13 Jun 2023, Paul Eggert wrote:

> > There is always the possibility to have the header co-owned by both
> > the compiler and C library, limits.h style.
> > Just
> > #if __has_include_next(<stdckdint.h>)
> > # include_next <stdckdint.h>
> > #endif
> 
> I don't see how you could implement __has_include_next(<stdckdint.h>) for
> arbitrary non-GCC compilers, which is what we'd need for glibc users. For
> glibc internals we can use "#include_next" more readily, since we assume a
> new-enough GCC. I.e. we could do something like this:

Given the possibility of library functions being included in <stdckdint.h> 
in future standard versions, it seems important to look at ways of 
splitting responsibility for the header between the compiler and library, 
whether with __has_include_next, or compiler version conditionals, or some 
other such variation.

-- 
Joseph S. Myers
joseph@codesourcery.com