From: Juanma Barranquero <lekktu@gmail.com>
To: Paul Eggert <eggert@cs.ucla.edu>
Cc: 8545@debbugs.gnu.org
Subject: bug#8545: issues with recent doprnt-related changes
Date: Thu, 28 Apr 2011 05:42:32 +0200 [thread overview]
Message-ID: <BANLkTi=UGn8bKrixk5HmqbO4psPNNSjw0A@mail.gmail.com> (raw)
In-Reply-To: <4DB8DAF8.7070408@cs.ucla.edu>
On Thu, Apr 28, 2011 at 05:11, Paul Eggert <eggert@cs.ucla.edu> wrote:
>> would it be undefined behavior,
>> as long as the pointer has not been dereferenced?
>
> Yes. A portable C program is not allowed to create a pointer that
> doesn't point to an object, with the two exceptions of a null pointer
> and a pointer to the address immediately after an object.
That's weird, because it would mean that every pointer variable must
be initialized (either explicitly to some value, or implicitly to the
null pointer), or else the program will have undefined behavior.
Anyway, in this case fmt == format_end + 1 would point to the address
immediately after an object, wouldn't it?
> On
> some architectures, attempting to point to random addresses can cause
> exceptions or other undefined behavior.
On dereferencing, sure. But just on assignment to the pointer variable?
Juanma
next prev parent reply other threads:[~2011-04-28 3:42 UTC|newest]
Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-25 5:46 bug#8545: issues with recent doprnt-related changes Paul Eggert
2011-04-25 9:00 ` Eli Zaretskii
2011-04-25 13:37 ` Stefan Monnier
2011-04-26 20:25 ` Paul Eggert
2011-04-27 1:14 ` Stefan Monnier
2011-04-26 6:02 ` Paul Eggert
2011-04-27 19:34 ` Eli Zaretskii
2011-04-27 23:51 ` Paul Eggert
2011-04-28 1:32 ` Juanma Barranquero
2011-04-28 3:11 ` Paul Eggert
2011-04-28 3:42 ` Juanma Barranquero [this message]
2011-04-28 5:06 ` Paul Eggert
2011-04-28 5:15 ` Eli Zaretskii
2011-04-28 5:29 ` Paul Eggert
2011-04-28 6:10 ` Eli Zaretskii
2011-04-28 6:42 ` Paul Eggert
2011-04-28 7:26 ` Eli Zaretskii
2011-04-28 7:54 ` Paul Eggert
2011-04-28 11:14 ` Eli Zaretskii
2011-04-29 12:28 ` Richard Stallman
2011-04-29 19:56 ` Eli Zaretskii
2011-04-29 23:49 ` Paul Eggert
2011-04-30 21:03 ` Richard Stallman
2011-05-01 5:41 ` Paul Eggert
2011-05-01 23:59 ` Richard Stallman
2011-05-02 0:23 ` Paul Eggert
[not found] ` <E1QH37h-0001yM-HR@fencepost.gnu.org>
2011-05-03 20:24 ` Paul Eggert
2011-05-01 4:25 ` Jason Rumney
2011-05-01 5:56 ` Paul Eggert
2011-05-01 8:12 ` Jason Rumney
2011-05-01 11:02 ` Andreas Schwab
2011-04-28 5:02 ` Eli Zaretskii
2011-04-28 5:50 ` Eli Zaretskii
[not found] ` <4DB9146D.2040702@cs.ucla.edu>
[not found] ` <E1QFQVO-0004Dq-6o@fencepost.gnu.org>
[not found] ` <4DB9E5FF.9020506@cs.ucla.edu>
2011-04-29 11:16 ` Eli Zaretskii
2011-04-29 14:41 ` Paul Eggert
2011-04-29 19:35 ` Eli Zaretskii
2011-04-29 20:32 ` Paul Eggert
2011-04-30 8:59 ` Eli Zaretskii
2011-05-04 7:28 ` Paul Eggert
2011-05-04 9:52 ` Eli Zaretskii
2011-05-04 14:56 ` Paul Eggert
2011-05-04 14:56 ` Paul Eggert
2011-05-05 20:36 ` bug#8545: " Eli Zaretskii
2011-05-05 20:36 ` Eli Zaretskii
2011-05-06 13:33 ` Stefan Monnier
2011-05-06 14:41 ` bug#8545: " Paul Eggert
2011-05-06 14:41 ` Paul Eggert
2011-05-06 15:03 ` bug#8545: " Eli Zaretskii
2011-05-06 15:03 ` Eli Zaretskii
2011-05-06 17:13 ` Stefan Monnier
2011-05-06 19:57 ` Eli Zaretskii
2011-05-07 3:18 ` bug#8545: " Stefan Monnier
2011-05-07 3:18 ` Stefan Monnier
2011-05-07 7:55 ` bug#8545: " Eli Zaretskii
2011-05-07 7:55 ` Eli Zaretskii
2011-05-06 19:57 ` bug#8545: " Eli Zaretskii
2011-05-06 17:13 ` Stefan Monnier
2011-05-06 13:33 ` Stefan Monnier
-- strict thread matches above, loose matches on Subject: below --
2011-05-01 18:19 bug#8601: * 2 -> * 4 typo fix in detect_coding_charset Paul Eggert
2011-05-01 19:06 ` Andreas Schwab
2011-05-01 19:25 ` Paul Eggert
2011-05-06 7:29 ` bug#8601: Merged fixes for 8600, 8601, 8602, and (partially) for 8545 Paul Eggert
2020-09-14 12:37 ` bug#8545: " Lars Ingebrigtsen
2020-09-14 18:41 ` Eli Zaretskii
2020-09-16 2:01 ` Paul Eggert
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