public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug c++/57857] New: argument of decltype used by no return value warning
@ 2013-07-09 2:42 potswa at mac dot com
2013-07-09 2:46 ` [Bug c++/57857] " potswa at mac dot com
2021-08-04 19:27 ` pinskia at gcc dot gnu.org
0 siblings, 2 replies; 3+ messages in thread
From: potswa at mac dot com @ 2013-07-09 2:42 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57857
Bug ID: 57857
Summary: argument of decltype used by no return value warning
Product: gcc
Version: 4.9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: potswa at mac dot com
The following program complains that "declval() must not be used!" in a static
assertion if -Wall is passed. But declval() is only present in the unevaluated
context of a decltype specifier.
The issue seems to be linked to the generation of the warning message. But the
warning message will be present without the static_assert if the function has
more than one exit point, such as if(0) throw; or if(0) return; (the latter
using -fpermissive).
#include <utility>
template <typename U>
auto foo() -> decltype(std::declval<U>() + std::declval<U>());
template <typename T>
decltype(foo<T>()) bar(T) {
// if ( 0 ) throw;
}
int main()
{ bar(1); }
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-08-04 19:27 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2013-07-09 2:42 [Bug c++/57857] New: argument of decltype used by no return value warning potswa at mac dot com
2013-07-09 2:46 ` [Bug c++/57857] " potswa at mac dot com
2021-08-04 19:27 ` pinskia at gcc dot gnu.org
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).