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From: "basv@odd-e.com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/94671] Wrong behavior with operator new overloading when using O2 for optimization
Date: Mon, 20 Apr 2020 13:25:41 +0000	[thread overview]
Message-ID: <bug-94671-4-C5dQQPw1Ot@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-94671-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94671

--- Comment #4 from Bas Vodde <basv@odd-e.com> ---

The newCalled to true in the example was the simplest way to show the behavior.

This bug came up in a open source project called CppuTest. This has the
functionality to detect memory leaks and does so by overloading the operator
new. For each operator new, it keeps accounting information.

When an operator new gets optimized by the compiler, the framework can't keep
track of the accounting information and the delete call will report that
non-allocated memory was deleted.

I assume this is an useful and perfectly legit way of overloading operator
new/delete.

This behavior was caught when running the automated test of the framework,
which failed in the debian build when updating to gcc10:
https://people.debian.org/~doko/logs/gcc10-20200225/cpputest_3.8-7_unstable_gcc10.log

  parent reply	other threads:[~2020-04-20 13:25 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-20 13:03 [Bug c++/94671] New: " basv@odd-e.com
2020-04-20 13:12 ` [Bug c++/94671] " redi at gcc dot gnu.org
2020-04-20 13:15 ` basv@odd-e.com
2020-04-20 13:17 ` rguenth at gcc dot gnu.org
2020-04-20 13:25 ` basv@odd-e.com [this message]
2020-04-20 13:31 ` basv@odd-e.com
2020-04-20 13:36 ` jakub at gcc dot gnu.org
2020-04-20 13:55 ` redi at gcc dot gnu.org
2020-04-20 14:23 ` redi at gcc dot gnu.org
2020-04-21  0:40 ` basv@odd-e.com

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