https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101883
Bug ID: 101883
Summary: class template argument deduction in non-type template
parameter allows explicit deduction guide
Product: gcc
Version: 10.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: barry.revzin at gmail dot com
Target Milestone: ---
Reduced example:
template <class T> struct C { constexpr C(int) {} };
explicit C(int) -> C<int>;
template <C c> struct X { };
X<1> x;
This should fail to compile, because the deduction guide is explicit and so
should not be a candidate, but gcc accepts this example.
gcc does correctly reject:
C y = 1;
Which is the same kind of thing.
