https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86471
--- Comment #26 from Matt Bentley <mattreecebentley at gmail dot com> --- (In reply to Jonathan Wakely from comment #25) > What warning? Why can't you just pass 0 to __builtin_memset? It's a null > pointer constant. I don't see any warning from clang when using -Weverything. As corrected above, clang only issues the warning when comparing NULL to 0 without static_cast or reinterpret_cast. > reinterpet_cast is forbidden in constexpr functions because it's purpose is > to break the type system and say "trust me, I know what I'm doing", and such > tricks are not allowed in constant expressions. Yeah, but... why > Using reinterpert_cast to convert 0 (a null pointer constant) into a pointer > type is just silly and poor style. That conversion can be done implicitly, > it doesn't need a sledgehammer to be used. That's a bit of silly hyperbole I can do without. > > But __builtin_constant_p allows it, so it's use is a matter of programmer > > choice, at least in this context. > > It really isn't if the standard requires the algorithm to be 'constexpr' > (which we don't implement yet, but there's no point adding constructs which > will just make life harder in the future). Fair enough- M@
