From: Ville Voutilainen <ville.voutilainen@gmail.com>
To: Jason Merrill <jason@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>,
gcc-patches List <gcc-patches@gcc.gnu.org>
Subject: Re: C++ PATCH for c++/88136, -Wdeprecated-copy too noisy
Date: Sat, 08 Dec 2018 18:05:00 -0000 [thread overview]
Message-ID: <CAFk2RUaH+xwVu9qL3qrP1d3ERhgBVb+pYjBbQ6BqtwNjM0+9cA@mail.gmail.com> (raw)
In-Reply-To: <CADzB+2kYU7S9y=CcgKr_7vuwRqsv11Q7HVhRrN_dMudT-1aEnA@mail.gmail.com>
On Sat, 8 Dec 2018 at 19:53, Jason Merrill <jason@redhat.com> wrote:
> The documented policy for -Wall is,
>
> This enables all the warnings about constructions that some users
> consider questionable, and that are easy to avoid (or modify to
> prevent the warning), even in conjunction with macros.
> ...
> Note that some warning flags are not implied by '-Wall'. Some of
> them warn about constructions that users generally do not consider
> questionable, but which occasionally you might wish to check for;
> others warn about constructions that are necessary or hard to avoid
> in some cases, and there is no simple way to modify the code to
> suppress the warning.
>
> It seems to me that this warning qualifies for -Wall under these
> guidelines. Providing a copy constructor without a matching
> assignment operator is definitely suspect; the false positive only
> comes in because, as you say, there was no good reason to provide the
> copy constructor for Private. And it's easy to avoid the warning by
> declaring a defaulted assignment operator, if ABI concerns preclude
> removing the constructor.
>
> New compiler releases will usually include new warnings that require
> some code modification to accommodate. Why is this one particularly
> problematic?
I don't think it's any more problematic than any other warning that
introduces new errors for fools that build with -Wall and -Werror.
But considering that those errors are false positives, and that
turning them off will in some cases require writing boiler-plate
(defaulted assignments), I would merely prefer having another release
round to get fixes for my codebase out in the wild.
next prev parent reply other threads:[~2018-12-08 18:05 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-06 21:12 Jason Merrill
2018-12-08 16:46 ` Ville Voutilainen
2018-12-08 16:58 ` Jakub Jelinek
2018-12-08 17:17 ` Ville Voutilainen
2018-12-08 17:53 ` Jason Merrill
2018-12-08 18:05 ` Ville Voutilainen [this message]
2018-12-08 18:33 ` Ville Voutilainen
2018-12-12 14:52 ` Jason Merrill
2018-12-12 15:30 ` Ville Voutilainen
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