From: "François Dumont" <frs.dumont@gmail.com>
To: libstdc++ <libstdc++@gcc.gnu.org>
Subject: PR 108846 regression
Date: Mon, 3 Apr 2023 21:59:50 +0200 [thread overview]
Message-ID: <ab398aa1-4384-714d-6cf2-238549799722@gmail.com> (raw)
After a full rebuild and run of testsuite based on master I have this
regression:
FAIL: 23_containers/vector/bool/allocator/copy.cc (test for excess errors)
Excess errors:
/home/fdumont/dev/gcc/build/x86_64-pc-linux-gnu/libstdc++-v3/include/bits/stl_algobase.h:437:
warning: 'void* __builtin_memmove(void*, const void*, long unsigned
int)' writing between 9 and 9223372036854775807 bytes into a region of
size 8 overflows the destination [-Wstringop-overflow=]
It comes from the change related to PR 108846, revision
822a11a1e642e0abe92a996e7033a5066905a447
The compiler seems to have enough info to find out that destination
memory area is 8 bytes large but not enough to see that _Num is 1 and so
never going to call the __builtin_memmove. Maybe a compiler bug.
I'm working on a patch to restore previous code when src and dst pointer
types are the same.
But I won't be able to continue my work on it before Wednesday so I
prefer to let you know just in case you would like to fix it before that
and maybe differently.
François
next reply other threads:[~2023-04-03 19:59 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-04-03 19:59 François Dumont [this message]
2023-04-03 20:06 ` Jonathan Wakely
2023-04-05 17:03 ` François Dumont
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=ab398aa1-4384-714d-6cf2-238549799722@gmail.com \
--to=frs.dumont@gmail.com \
--cc=libstdc++@gcc.gnu.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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).