https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97207
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
OK, so
diff --git a/gcc/vec.c b/gcc/vec.c
index a28899170ed..0cda3b96beb 100644
--- a/gcc/vec.c
+++ b/gcc/vec.c
@@ -560,6 +560,9 @@ vec_c_tests ()
test_qsort ();
test_reverse ();
test_auto_delete_vec ();
+ auto_vec<int> a;
+ auto_vec<int> b;
+ std::swap (a, b);
}
} // namespace selftest
produces a similar error:
/home/rguenther/src/gcc3/gcc/vec.c: In function 'void selftest::vec_c_tests()':
/home/rguenther/src/gcc3/gcc/vec.c:565:18: error: no matching function for call
to 'swap(auto_vec<int>&, auto_vec<int>&)'
std::swap (a, b);
^
In file included from /usr/include/c++/7/bits/nested_exception.h:40:0,
from /usr/include/c++/7/exception:143,
from /usr/include/c++/7/new:40,
from /home/rguenther/src/gcc3/gcc/system.h:236,
from /home/rguenther/src/gcc3/gcc/vec.c:30:
/usr/include/c++/7/bits/move.h:187:5: note: candidate: template<class _Tp>
typename std::enable_if<std::__and_<std::__not_<std::__is_tuple_like<_Tp> >,
std::is_move_constructible<_Tp>, std::is_move_assignable<_Tp> >::value>::type
std::swap(_Tp&, _Tp&)
swap(_Tp& __a, _Tp& __b)
^~~~
/usr/include/c++/7/bits/move.h:187:5: note: template argument
deduction/substitution failed:
/usr/include/c++/7/bits/move.h: In substitution of 'template<class _Tp>
typename std::enable_if<std::__and_<std::__not_<std::__is_tuple_like<_Tp> >,
std::is_move_constructible<_Tp>, std::is_move_assignable<_Tp> >::value>::type
std::swap(_Tp&, _Tp&) [with _Tp = auto_vec<int>]':
/home/rguenther/src/gcc3/gcc/vec.c:565:18: required from here
/usr/include/c++/7/bits/move.h:187:5: error: no type named 'type' in 'struct
std::enable_if<false, void>'
/usr/include/c++/7/bits/move.h:210:5: note: candidate: template<class _Tp, long
unsigned int _Nm> typename
std::enable_if<std::__is_swappable<_Tp>::value>::type std::swap(_Tp (&)[_Nm],
_Tp (&)[_Nm])
swap(_Tp (&__a)[_Nm], _Tp (&__b)[_Nm])
^~~~
/usr/include/c++/7/bits/move.h:210:5: note: template argument
deduction/substitution failed:
/home/rguenther/src/gcc3/gcc/vec.c:565:18: note: mismatched types '_Tp [_Nm]'
and 'auto_vec<int>'
std::swap (a, b);
^
In file included from /usr/include/c++/7/utility:70:0,
from /home/rguenther/src/gcc3/gcc/system.h:237,
from /home/rguenther/src/gcc3/gcc/vec.c:30:
/usr/include/c++/7/bits/stl_pair.h:495:5: note: candidate: template<class _T1,
class _T2> typename std::enable_if<std::__and_<std::__is_swappable<_T1>,
std::__is_swappable<_T2> >::value>::type std::swap(std::pair<_T1, _T2>&,
std::pair<_T1, _T2>&)
swap(pair<_T1, _T2>& __x, pair<_T1, _T2>& __y)
^~~~
/usr/include/c++/7/bits/stl_pair.h:495:5: note: template argument
deduction/substitution failed:
/home/rguenther/src/gcc3/gcc/vec.c:565:18: note: 'auto_vec<int>' is not
derived from 'std::pair<_T1, _T2>'
std::swap (a, b);
^
In file included from /usr/include/c++/7/utility:70:0,
from /home/rguenther/src/gcc3/gcc/system.h:237,
from /home/rguenther/src/gcc3/gcc/vec.c:30:
/usr/include/c++/7/bits/stl_pair.h:503:5: note: candidate: template<class _T1,
class _T2> typename std::enable_if<(! std::__and_<std::__is_swappable<_T1>,
std::__is_swappable<_T2> >::value)>::type std::swap(std::pair<_T1, _T2>&,
std::pair<_T1, _T2>&) <deleted>
swap(pair<_T1, _T2>&, pair<_T1, _T2>&) = delete;
^~~~
/usr/include/c++/7/bits/stl_pair.h:503:5: note: template argument
deduction/substitution failed:
/home/rguenther/src/gcc3/gcc/vec.c:565:18: note: 'auto_vec<int>' is not
derived from 'std::pair<_T1, _T2>'
std::swap (a, b);
^
make: *** [Makefile:1123: vec.o] Error 1
IMHO looks like a libstdc++ bug to me?
