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From: Florian Weimer <fweimer@redhat.com>
To: "Carlos O'Donell" <carlos@redhat.com>,
	GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [PATCH] Fix -Os related -Werror failures.
Date: Fri, 28 Oct 2016 06:32:00 -0000	[thread overview]
Message-ID: <6be7dce5-bfa7-32c7-5bac-6c3b79776683@redhat.com> (raw)
In-Reply-To: <6eac682f-26fa-6a47-9497-357206266ba1@redhat.com>

On 10/28/2016 06:46 AM, Carlos O'Donell wrote:
> +/* With GCC 5.3 when compiling with -Os the compiler emits a warning
> +   that buf[0] and buf[1] may be used uninitialized.  This can only
> +   happen in the case where tmpbuf[3] is used, and in that case the
> +   write to the tmpbuf[1] and tmpbuf[2] was assured because
> +   ucs4_to_cns11643 would have filled in those entries.  The difficulty
> +   is in getting the compiler to see this logic because tmpbuf[0] is
> +   involved in determining the code page and is the indicator that
> +   tmpbuf[2] is initialized.  */
> +DIAG_PUSH_NEEDS_COMMENT;
> +DIAG_IGNORE_NEEDS_COMMENT (5.3, "-Wmaybe-uninitialized");

This hides the warning for -O2 builds as well, so I don't think this is 
a good idea.

Those who want to build with -Os or other special compiler flags should 
just configure with --disable-werror.  We can't account for every 
optimization someone might want to disable in their build.

Florian

  parent reply	other threads:[~2016-10-28  6:32 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-28  4:48 Carlos O'Donell
2016-10-28  6:25 ` Andreas Schwab
2016-10-28  6:32 ` Florian Weimer [this message]
2016-10-28  6:44   ` Jeff Law
2016-10-28  8:12     ` Arnd Bergmann
2016-10-28  8:17       ` Andrew Pinski
2016-10-28 13:28         ` Jeff Law
2016-10-28 20:10       ` Paul Eggert
2016-10-29  3:03         ` Jeff Law
2016-10-30  4:25           ` Paul Eggert
2016-10-28 12:09   ` Carlos O'Donell
2016-10-28 12:43     ` Florian Weimer
2016-10-28 13:04     ` Joseph Myers
2016-10-28 13:07     ` Carlos O'Donell
2016-10-28 12:49   ` Joseph Myers
2016-10-28 12:55     ` Florian Weimer
2016-10-28 13:18       ` Carlos O'Donell
2016-10-28 13:58         ` [PATCH v2] Fix -Os related build and test failures Carlos O'Donell
2016-10-28 14:17           ` Joseph Myers
2016-10-29  2:59             ` [PATCH v3] " Carlos O'Donell
2016-10-29  3:26               ` Carlos O'Donell
2016-10-29 17:35               ` Joseph Myers
2016-10-30  3:51                 ` [PATCH v4] " Carlos O'Donell
2016-10-31  8:33                   ` Andreas Schwab
2016-10-31  9:16                     ` Carlos O'Donell
2016-10-31  9:22                       ` Florian Weimer
2016-10-31 12:56                       ` David Miller
2016-10-31 19:56                         ` Carlos O'Donell
2016-11-01 22:59                           ` Joseph Myers
2016-11-02 12:52                             ` Carlos O'Donell
2016-11-01  9:17                   ` Andreas Schwab
2016-11-01 11:13                     ` Joseph Myers
2016-11-01 15:58                       ` Tamar Christina
2016-11-01 16:06                         ` David Miller
2016-11-01 16:15                           ` Tamar Christina
2016-11-02 11:53                           ` Carlos O'Donell
2016-11-02 17:03                             ` Carlos O'Donell
2016-11-02 13:22                       ` Carlos O'Donell
2016-10-31 18:38               ` [PATCH v3] " Steve Ellcey
2016-10-31 19:50                 ` Carlos O'Donell
2016-10-31 19:57                   ` Steve Ellcey
2016-10-31 20:50                     ` Carlos O'Donell
2016-10-31 21:00                       ` Steve Ellcey

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