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From: "kdevel at vogtner dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/43943] "warning: no return statement in function returning non-void" should be an error
Date: Tue, 19 Apr 2022 09:55:16 +0000 [thread overview]
Message-ID: <bug-43943-4-W2ywAyY9Ay@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-43943-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43943
Stefan <kdevel at vogtner dot de> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |kdevel at vogtner dot de
--- Comment #8 from Stefan <kdevel at vogtner dot de> ---
(In reply to Jonathan Wakely from comment #4)
> There are cases which are either not diagnosable or cannot be
> written, such as this example from Doug Gregor:
>
> in generic code, there might not be a way to create a value with the
> appropriate type. For example:
>
> template<typename T>
> T maybe_call(std::function<T(void)> f) {
> if (f)
> return f();
> else
> abort_program();
>
> // Cannot write a return here, because we have no way to
> create a value of type 'T'
> }
One can of course write a return there:
template<typename T>
T maybe_call(std::function<T(void)> f)
{
if (f)
return f();
else
abort_program();
// Cannot write a return here, because we have no way to create a value
of type 'T'
return f();
}
which refactors nicely into
template<typename T>
T maybe_call(std::function<T(void)> f)
{
if (! f)
abort_program();
return f();
}
next prev parent reply other threads:[~2022-04-19 9:55 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <bug-43943-4@http.gcc.gnu.org/bugzilla/>
2020-04-26 9:44 ` redi at gcc dot gnu.org
2022-04-19 9:55 ` kdevel at vogtner dot de [this message]
2023-03-31 18:38 ` pinskia at gcc dot gnu.org
2010-04-29 20:13 [Bug c++/43943] New: " david at rothlis dot net
2010-04-29 20:32 ` [Bug c++/43943] " pinskia at gcc dot gnu dot org
2010-04-29 20:36 ` redi at gcc dot gnu dot org
2010-04-30 6:05 ` david at rothlis dot net
2010-04-30 11:22 ` redi at gcc dot gnu dot org
2010-04-30 11:26 ` redi at gcc dot gnu dot org
2010-04-30 14:01 ` david at rothlis dot net
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