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Date: Thu, 3 Nov 2022 15:19:25 +0000 (UTC)
From: Michael Matz <matz@suse.de>
To: Florian Weimer <fweimer@redhat.com>
cc: gcc@gcc.gnu.org
Subject: Re: Local type inference with auto is in C2X
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Hello,

On Thu, 3 Nov 2022, Florian Weimer via Gcc wrote:

> will not have propagated widely once GCC 13 releases, so rejecting
> implicit ints in GCC 13 might be too early.  GCC 14 might want to switch
> to C23/C24 mode by default, activating auto support, if the standard
> comes out in 2023 (which apparently is the plan).
> 
> Then we would go from
> warning to changed semantics in a single release.
> 
> Comments?

I would argue that changing the default C mode to c23 in the year that 
comes out (or even a year later) is too aggressive and early.  Existing 
sources are often compiled with defaults, and hence would change 
semantics, which seems unattractive.  New code can instead easily use 
-std=c23 for a time.

E.g. c99/gnu99 (a largish deviation from gnu90) was never default and 
gnu11 was made default only in 2014.


Ciao,
Michael.