[PATCH] D40218: [Clang] Add __builtin_launder

[Jonathan Roelofs via Phabricator via cfe-commits]

jroelofs added inline comments.


================
Comment at: include/clang/Basic/Builtins.def:480
 BUILTIN(__builtin_thread_pointer, "v*", "nc")
+BUILTIN(__builtin_launder, "v*v*", "nt")
 
----------------
EricWF wrote:
> jroelofs wrote:
> > GCC's is type-generic:
> > 
> > ```
> > #include <type_traits>
> > 
> > bool is_type_generic() {
> >   int v;
> >   return std::is_same<decltype(__builtin_launder(&v)),
> >                       decltype(&v)>::value;
> > }
> > ```
> > 
> > However this `BUILTIN` line says that this one is not (yeah, I see it's being fixed up in Sema later in this patch). I think you need to use custom type checking here via `t`.
> The `t` is specified. It's in the third argument. 
ohhh. duh. sorry.


https://reviews.llvm.org/D40218