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From: "glisse at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/94295] use __builtin_operator_new and
 __builtin_operator_delete when available
Date: Tue, 24 Mar 2020 07:04:10 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94295

--- Comment #1 from Marc Glisse <glisse at gcc dot gnu.org> ---
(In reply to Richard Smith from comment #0)
> The C++ language rules do not permit optimization (eg, deletion) of direct
> calls to 'operator new' and 'operator delete'.

I thought that was considered a bug?
Gcc does optimize those, like it does malloc/free...

> This bug requests that libstdc++ uses these builtins when available.

So just in std::allocator, or are there other places?

> (Separately, it'd be great if GCC considered supporting them too.)

IIRC (would need to dig up the conversation), when the optimization for
new/delete pairs was added in gcc, the builtin option was rejected.=