https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89287
Bug ID: 89287
Summary: Array declaration fails to use template conversion
operator
Product: gcc
Version: 8.2.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: raphael.kubo.da.costa at intel dot com
Target Milestone: ---
(This is a reduction from a GCC + Chromium build issue)
Building the following excerpt with -std=gnu++14 causes GCC to fail, while
MSVC, clang and ICC work fine:
struct S {
template <class U>
constexpr operator U() const {
return static_cast<U>(42);
}
};
void frob() {
new char[S()];
}
x.cc: In function ‘void frob()’:
x.cc:9:14: error: default type conversion can't deduce template argument for
‘template<class U> constexpr S::operator U() const’
new char[S()];
^
C++14 says in 8.3.4 Arrays that "If the constant-expression (5.20) is present,
it shall be a converted constant expression of type std::size_t and its value
shall be greater than zero", so I was expecting `new char[S()]' to end up
invoking S::operator size_t().
