[Bug c++/82304] GCC compiles constexpr function with double reinterpret_cast in a constant context

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82304

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2017-09-25 00:00:00         |2019-11-28

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Reduced:

constexpr const char* testfunc(const char* p)
{
  auto l = reinterpret_cast<unsigned long long>(p);
  ++l
  return reinterpret_cast<const char*>(l);
}

constexpr auto s = testfunc("Hello");

I assume the problem here and in Bug 92411 is that the compiler is folding the
casts away.