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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/98753] -Wfree-nonheap-object on Bison generated code
Date: Wed, 20 Jan 2021 07:31:49 +0000	[thread overview]
Message-ID: <bug-98753-4-rn3UJFuhgD@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-98753-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98753

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
The issue is that we isolate a path that is impossible to take but on that
path we have p = &foo; free (p); and thus a "proved" mistake.  But in
reality it is guarded by an effective if (false) condition.  So it's not as
simple as you think.  (we also emit diagnostics on function bodies we do not
know are actually never called)

  parent reply	other threads:[~2021-01-20  7:31 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-19 20:18 [Bug c++/98753] New: " foss at grueninger dot de
2021-01-19 20:55 ` [Bug c++/98753] " msebor at gcc dot gnu.org
2021-01-20  5:22 ` akim.demaille at gmail dot com
2021-01-20  7:31 ` rguenth at gcc dot gnu.org [this message]
2021-01-20  7:40 ` foss at grueninger dot de
2021-01-20 16:48 ` msebor at gcc dot gnu.org
2021-01-20 17:00 ` foss at grueninger dot de
2021-01-20 17:34 ` [Bug middle-end/98753] -Wfree-nonheap-object on unreachable code with -O0 msebor at gcc dot gnu.org
2021-01-20 17:34 ` akim.demaille at gmail dot com
2021-01-20 17:40 ` akim.demaille at gmail dot com
2021-01-26 19:37 ` slyfox at gcc dot gnu.org
2021-01-29 11:29 ` boris at kolpackov dot net
2021-01-29 11:30 ` boris at kolpackov dot net
2021-01-29 11:30 ` boris at kolpackov dot net
2021-01-29 11:36 ` boris at kolpackov dot net
2021-01-29 16:48 ` msebor at gcc dot gnu.org
2024-01-02 16:08 ` stefan at bytereef dot org

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