https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63437
Bug ID: 63437
Summary: [4.9/5 regression][C++14] Parenthesized "movable but
not copyable" object doesn't compile in return
statement
Product: gcc
Version: 4.9.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: flast at flast dot jp
After GCC 4.9, parenthesized "movable but not copyable" object doesn't compile
in return statement under C++14 mode (C++11 mode does compile).
I'm not sure that the behavior was changed in C++14 spec; Clang seems compile
under both of C++11/14 mode.
example:
----
struct X // movable but not copyable
{
X() = default;
X(X &&) = default;
X(const X &) = delete;
};
X non_parenthesized()
{
X x;
return x; // works
}
X parenthesized()
{
X x;
return (x); // error: use of deleted function 'X::X(const X&)'
}
----
Online compiler results:
- GCC 4.8.2
- C++11 http://melpon.org/wandbox/permlink/lRR60fvDgKfqd0UZ
- C++14 http://melpon.org/wandbox/permlink/BAdrBmEG3euQLnqv
- GCC 4.9.1
- C++11 http://melpon.org/wandbox/permlink/XllfUNu0VV0mnYsu
- C++14 http://melpon.org/wandbox/permlink/qm67F6vODyADgKvQ (fail)
- GCC 5.0 20141001
- C++11 http://melpon.org/wandbox/permlink/21bPbcuXB7S87DUG
- C++14 http://melpon.org/wandbox/permlink/da8AeqX7HrS17T2n (fail)
- Clang 3.5.0
- C++11 http://melpon.org/wandbox/permlink/VqgnlKRTOBHd5IDt
- C++14 http://melpon.org/wandbox/permlink/tAkgLiaD50nOMtEz
