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From: "marc-andre.laverdiere at synopsys dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/109305] Allocator copy in basic_string::operator=
Date: Tue, 28 Mar 2023 16:04:08 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109305

--- Comment #4 from Marc-Andr=C3=A9 Laverdi=C3=A8re <marc-andre.laverdiere =
at synopsys dot com> ---
The comment is "If this allocation throws there are no effects:" and I didn=
't
understand the implications. Thanks for you spelled it out the logic behind=
 it.
May I encourage you to update the comment?

As to why a local copy could be a problem, it's an efficiency (rather than
correctness) issue here. Removing unnecessary copies is always a plus. From=
 the
explanations I got, that copy is necessary - or at least, removing it would=
 be
complex.=