From: "Dmitry V. Levin" <ldv@altlinux.org>
To: Ivan Zakharyaschev <imz@altlinux.org>
Cc: darktemplar@altlinux.org, devel@lists.altlinux.org
Subject: Re: [devel] [APT PATCH] rpmSingle{Pkg, Src}Index::ArchiveURI(): avoid cases with undefined behavior
Date: Sun, 16 Feb 2020 14:17:00 +0300
Message-ID: <20200216111659.GA26792@altlinux.org> (raw)
In-Reply-To: <alpine.LFD.2.20.2002160401421.6363@imap.altlinux.org>
On Sun, Feb 16, 2020 at 04:09:14AM +0300, Ivan Zakharyaschev wrote:
> Two cases of UB are avoided with such a rewrite:
>
> * getcwd(2) returned NULL. Constructing a string from NULL is UB.
> (Such string was passed as an argument to flCombine().)
> Now, SafeGetCwd() (in fileutl.cc) returns "/" in such cases;
> if you consider SafeGetCwd()'s implementation not to be reasonable,
> rewrite it (just at a single place).
ack
> * File.length() < 2. Since File was a non-const string,
> File[File.length()] might be UB before C++11. Now, File is const, and
> it is guaranteed that File[File.length()] == 0.
We can safely assume C++11, but I don't think we have an UB here even
before C++11. Anyway, this part of the change is better covered by
"Avoid copying objects" patch.
--
ldv
next prev parent reply other threads:[~2020-02-16 11:17 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-16 1:09 Ivan Zakharyaschev
2020-02-16 11:17 ` Dmitry V. Levin [this message]
2020-02-16 17:25 ` [devel] [nitpick] " Michael Shigorin
2020-02-17 0:39 ` [devel] " Ivan Zakharyaschev
2020-02-18 1:55 ` Ivan Zakharyaschev
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200216111659.GA26792@altlinux.org \
--to=ldv@altlinux.org \
--cc=darktemplar@altlinux.org \
--cc=devel@lists.altlinux.org \
--cc=imz@altlinux.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
ALT Linux Team development discussions
This inbox may be cloned and mirrored by anyone:
git clone --mirror http://lore.altlinux.org/devel/0 devel/git/0.git
# If you have public-inbox 1.1+ installed, you may
# initialize and index your mirror using the following commands:
public-inbox-init -V2 devel devel/ http://lore.altlinux.org/devel \
devel@altlinux.org devel@altlinux.ru devel@lists.altlinux.org devel@lists.altlinux.ru devel@linux.iplabs.ru mandrake-russian@linuxteam.iplabs.ru sisyphus@linuxteam.iplabs.ru
public-inbox-index devel
Example config snippet for mirrors.
Newsgroup available over NNTP:
nntp://lore.altlinux.org/org.altlinux.lists.devel
AGPL code for this site: git clone https://public-inbox.org/public-inbox.git