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From: "aaron at aaronballman dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/107980] va_start does not warn about an arbitrary number of arguments in C2x mode
Date: Wed, 07 Dec 2022 16:42:46 +0000	[thread overview]
Message-ID: <bug-107980-4-YuFVto9NZ5@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-107980-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107980

--- Comment #16 from Aaron Ballman <aaron at aaronballman dot com> ---
(In reply to Andrew Pinski from comment #15)
> (In reply to Aaron Ballman from comment #14)
> > Also, it was a potentially silently breaking change (if you don't mind
> > horribly contrived examples of breakage): https://godbolt.org/z/T4bG6179f
> 
> But __COUNTER__ is not part of the standard ....

The code changed meaning regardless and WG14 usually goes out of our way to
avoid changing the meaning of existing, conforming code. (FWIW, I'll freely
admit this example is not compelling; it's just intended as a demonstration
that I don't think WG14 fully thought through the ramifications of what
prohibiting token expansion does in practice.)

  parent reply	other threads:[~2022-12-07 16:42 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-05 20:46 [Bug c/107980] New: va_start incorrectly accepts an arbitrary number of arguments in C2x aaron at aaronballman dot com
2022-12-05 20:57 ` [Bug c/107980] " pinskia at gcc dot gnu.org
2022-12-05 21:04 ` aaron at aaronballman dot com
2022-12-05 21:10 ` [Bug c/107980] va_start does not warn about an arbitrary number of arguments in C2x mode pinskia at gcc dot gnu.org
2022-12-05 21:17 ` pinskia at gcc dot gnu.org
2022-12-06 13:37 ` aaron at aaronballman dot com
2022-12-06 13:44 ` pinskia at gcc dot gnu.org
2022-12-06 13:51 ` jakub at gcc dot gnu.org
2022-12-06 14:04 ` aaron at aaronballman dot com
2022-12-06 15:42 ` aaron at aaronballman dot com
2022-12-06 15:46 ` jakub at gcc dot gnu.org
2022-12-06 16:13 ` aaron at aaronballman dot com
2022-12-07  0:55 ` joseph at codesourcery dot com
2022-12-07 14:57 ` jakub at gcc dot gnu.org
2022-12-07 15:00 ` aaron at aaronballman dot com
2022-12-07 15:38 ` pinskia at gcc dot gnu.org
2022-12-07 16:42 ` aaron at aaronballman dot com [this message]
2022-12-07 18:29 ` joseph at codesourcery dot com

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