Unexpected compile time error when forbidden rvalue operator const char*

[Alek86]

Maybe it's a known limitation, sorry for bothering in this case.
This code generates a compiler error (tried with VS 2015 and godbolt with clang 6.0.0):

#include <fmt/core.h>
class PString {
public:
    const char* c_str() const { return "11"; }
    operator const char*() const& { return c_str(); }
    operator const char*()& { return c_str(); }
    operator const char*() const&& = delete;
    operator const char*()&& = delete;
};
int main() {
    PString str;
    fmt::print("{}", str);
}

Not a big deal, because it's easily bypassed by adding code below. But maybe you want to address it anyway.

template <>
struct fmt::formatter<PString> {
  constexpr auto parse(format_parse_context& ctx) { return ctx.begin(); }
  template <typename FormatContext>
  auto format(const PString& ct, FormatContext& ctx) {
    return format_to(ctx.out(), "{}", ct.c_str());
  }
};

[vitaut]

Should be fixed in 99b6e92. Thanks for reporting.