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From: Kees Cook <keescook@chromium.org>
To: Qing Zhao <qing.zhao@oracle.com>
Cc: Richard Biener <rguenther@suse.de>,
	richard Sandiford <richard.sandiford@arm.com>,
	gcc-patches Qing Zhao via <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH][version 3]add -ftrivial-auto-var-init and variable attribute "uninitialized" to gcc
Date: Mon, 21 Jun 2021 09:18:45 -0700	[thread overview]
Message-ID: <202106210916.DCC72C72@keescook> (raw)
In-Reply-To: <E68B20D5-77D8-4343-9A3C-8B2E08EF3894@oracle.com>

On Mon, Jun 21, 2021 at 03:39:45PM +0000, Qing Zhao wrote:
> So, if “pattern value” is “0xFFFFFFFFFFFFFFFF”, then it’s a valid canonical virtual memory address.  However, for most OS, “0xFFFFFFFFFFFFFFFF” should be not in user space.
> 
> My question is, is “0xFFFFFFFFFFFFFFFFF” good for pointer? Or “0xAAAAAAAAAAAAAAAA” better?

I think 0xFF repeating is fine for this version. Everything else is a
"nice to have" for the pattern-init, IMO. :)

-- 
Kees Cook

  reply	other threads:[~2021-06-21 16:18 UTC|newest]

Thread overview: 57+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-12 17:16 Qing Zhao
2021-05-25 19:26 ` Qing Zhao
2021-05-26 11:18 ` Richard Biener
2021-05-27 19:44   ` Qing Zhao
2021-06-07  7:48     ` Richard Biener
2021-06-07 16:13       ` Qing Zhao
2021-06-08  7:37         ` Richard Biener
2021-06-08 16:56           ` Kees Cook
2021-06-08 17:32             ` Qing Zhao
2021-06-08 17:36               ` Kees Cook
2021-06-07 23:45       ` Kees Cook
2021-06-08  8:27         ` Richard Biener
2021-05-27 21:42   ` Qing Zhao
2021-06-03 20:14   ` Qing Zhao
2021-06-07  7:50     ` Richard Biener
2021-06-03 20:18   ` Qing Zhao
2021-06-07  7:53     ` Richard Biener
2021-06-07 16:18       ` Qing Zhao
2021-06-07 23:48         ` Kees Cook
2021-06-08  7:41         ` Richard Biener
2021-06-08 15:27           ` Qing Zhao
2021-06-08 16:59           ` Kees Cook
2021-06-08 18:05             ` Qing Zhao
2021-06-11 11:04             ` Richard Biener
2021-06-11 17:14               ` Kees Cook
2021-06-10 21:11   ` Qing Zhao
2021-06-11 11:12     ` Richard Biener
2021-06-11 15:49       ` Qing Zhao
2021-06-11 16:24         ` Kees Cook
2021-06-11 17:00         ` Qing Zhao
2021-06-14 16:10         ` Qing Zhao
2021-06-15 13:21           ` Richard Biener
2021-06-15 21:49             ` Qing Zhao
2021-06-16  6:19               ` Richard Biener
2021-06-16 15:04                 ` Qing Zhao
2021-06-16 19:39                   ` Qing Zhao
2021-06-18 23:47                     ` Kees Cook
2021-06-21 15:39                       ` Qing Zhao
2021-06-21 16:18                         ` Kees Cook [this message]
2021-06-21 17:11                           ` Qing Zhao
2021-06-22  8:25                           ` Richard Sandiford
2021-06-22  8:59                             ` Richard Biener
2021-06-22 13:54                               ` Qing Zhao
2021-06-22 14:00                                 ` Richard Biener
2021-06-22 14:10                                   ` Qing Zhao
2021-06-22 14:15                                     ` Richard Biener
2021-06-22 14:33                                       ` Qing Zhao
2021-06-22 19:04                                         ` Richard Biener
2021-06-22 17:55                             ` Kees Cook
2021-06-22 18:18                               ` Richard Sandiford
2021-06-22 21:31                                 ` Qing Zhao
2021-06-23  6:05                                   ` Richard Biener
2021-06-21  7:53                   ` Richard Biener
2021-06-21 15:11                     ` Qing Zhao
2021-06-21 15:35                       ` Richard Biener
2021-06-21 16:13                         ` Qing Zhao
2021-06-22  6:24                           ` Richard Biener

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