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From: Florian Weimer <fweimer@redhat.com>
To: libc-alpha@sourceware.org
Cc: Siddhesh Poyarekar <siddhesh@redhat.com>
Subject: C90 header compatibility
Date: Mon, 30 Jan 2023 08:58:19 +0100	[thread overview]
Message-ID: <871qnc1mjo.fsf@oldenburg.str.redhat.com> (raw)

We regressed compatibility with C90 compilers because <sys/cdefs.h>
unconditionally uses variadic macros, a C99 feature, in the definition
of __glibc_fortify and __glibc_fortify_n.

This also impacts certain C++ compilers that do not have a
C99-compatible preprocessor.

Should we fix this?  I think so.

Previously, we worked around this by enclosing variable-length lists in
(…), but it doesn't look like it might work here.  We probably need to
move the macros into a separate file, and include that file only if
fortification is active.

Thanks,
Florian


             reply	other threads:[~2023-01-30  7:58 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-30  7:58 Florian Weimer [this message]
2023-01-30 12:26 ` Siddhesh Poyarekar
2023-01-30 12:43   ` Florian Weimer
2023-01-30 13:32     ` [PATCH] cdefs: Limit definition of fortification macros Siddhesh Poyarekar
2023-02-01 17:48       ` Florian Weimer

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