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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/114220] False positive warning: possibly dangling reference to a temporary [-Wdangling-reference]
Date: Sun, 03 Mar 2024 08:33:40 +0000	[thread overview]
Message-ID: <bug-114220-4-XwWr6ZiUJD@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114220-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114220

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |INVALID

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
const std::string& z2(const std::string& m);

const std::string& z2(const std::string& m) { return hashTable2.at(m); }


  const std::string& b2 { z2("u") };


The warning is designed this way explictly because you are returning a
reference and taking a reference as an argument and in the case of b2, the
tempory is `std::string("u")` .

In GCC 14+ (since r14-9263-gc7607c4cf18986), you can add [[gnu::no_dangling]]
to the z2 function definition to mark it as not returning a dangling reference
(from the arguments). and the warning goes away.

  reply	other threads:[~2024-03-03  8:33 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-03  8:26 [Bug c++/114220] New: " dilyan.palauzov at aegee dot org
2024-03-03  8:33 ` pinskia at gcc dot gnu.org [this message]
2024-03-03 10:23 ` [Bug c++/114220] " dilyan.palauzov at aegee dot org
2024-03-03 10:30 ` dilyan.palauzov at aegee dot org
2024-03-03 18:37 ` pinskia at gcc dot gnu.org
2024-03-04  9:07 ` xry111 at gcc dot gnu.org

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