From: Jonathan Wakely <jwakely@redhat.com>
To: libstdc++@gcc.gnu.org, gcc-patches@gcc.gnu.org
Subject: [committed] libstdc++: Begin lifetime of storage in std::vector<bool> [PR114367]
Date: Tue, 19 Mar 2024 15:14:06 +0000 [thread overview]
Message-ID: <20240319151424.3382794-1-jwakely@redhat.com> (raw)
Tested x86_64-linux. Pushed to trunk. Backport to gcc-13 to follow.
-- >8 --
This doesn't cause a problem with GCC, but Clang correctly diagnoses a
bug in the code. The objects in the allocated storage need to begin
their lifetime before we start using them.
This change uses the allocator's construct function instead of using
std::construct_at directly, in order to support fancy pointers.
libstdc++-v3/ChangeLog:
PR libstdc++/114367
* include/bits/stl_bvector.h (_M_allocate): Use allocator's
construct function to begin lifetime of words.
---
libstdc++-v3/include/bits/stl_bvector.h | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/libstdc++-v3/include/bits/stl_bvector.h b/libstdc++-v3/include/bits/stl_bvector.h
index 2c8b892b07a..a3343d95b36 100644
--- a/libstdc++-v3/include/bits/stl_bvector.h
+++ b/libstdc++-v3/include/bits/stl_bvector.h
@@ -674,13 +674,13 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
_M_allocate(size_t __n)
{
_Bit_pointer __p = _Bit_alloc_traits::allocate(_M_impl, _S_nword(__n));
-#if __cpp_lib_is_constant_evaluated
+#if __cpp_lib_is_constant_evaluated && __cpp_constexpr_dynamic_alloc
if (std::is_constant_evaluated())
- {
- __n = _S_nword(__n);
- for (size_t __i = 0; __i < __n; ++__i)
- __p[__i] = 0ul;
- }
+ {
+ __n = _S_nword(__n);
+ for (size_t __i = 0; __i < __n; ++__i)
+ std::construct_at(std::to_address(__p) + __i);
+ }
#endif
return __p;
}
--
2.44.0
reply other threads:[~2024-03-19 15:14 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=20240319151424.3382794-1-jwakely@redhat.com \
--to=jwakely@redhat.com \
--cc=gcc-patches@gcc.gnu.org \
--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).