https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84782
Bug ID: 84782
Summary: Rejects a maybe C++ code snippet
Product: gcc
Version: unknown
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: marxin at gcc dot gnu.org
CC: jason at gcc dot gnu.org
Target Milestone: ---
We reject:
$ cat playback_image_provider.ii
template <typename a, a b> struct c { static constexpr a d = b; };
template <typename a> a ac();
template <typename a, typename e> class f {
template <typename g, typename, typename = decltype(ac<g>() = ac)>
void h(int);
template <typename, typename> static c<bool, false> h(...);
public:
typedef decltype(h<a, e>(0)) i;
};
template <typename a> struct j : f<a, int>::i {};
class k {
public:
k(const k &);
void operator=(k &&);
};
class l : k {
using ae = k;
using ae::operator=;
};
template <int> struct m {};
template <typename af> class n : m<j<af>::d> {};
class o {
struct G {
G(const G &);
l q;
};
n<G> p;
};
o::G::G(const G &) = default;
$ g++ -c playback_image_provider.ii
playback_image_provider.ii:30:1: note: ‘o::G::G(const o::G&)’ is implicitly
deleted because the default definition would be ill-formed:
o::G::G(const G &) = default;
^
playback_image_provider.ii:30:1: error: use of deleted function ‘l::l(const
l&)’
playback_image_provider.ii:17:7: note: ‘l::l(const l&)’ is implicitly declared
as deleted because ‘l’ declares a move constructor or move assignment operator
class l : k {
^
However clang accepts:
$ clang++ -c playback_image_provider.ii -std=c++11
