https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119376
--- Comment #15 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #14)
> Another one testcase:
> ```
> struct s1 {
> int t;
> };
> char *f1(int);
> char *f2(int a) {
> s1 t;
> asm("":"+m"(t));
> [[clang::musttail]] return f1(a);
> }
> ```
> But this is about escapability of t.
protobuf removed that "hack":
https://github.com/protocolbuffers/protobuf/commit/bc56c34007fb773342916b9d01711f9aa289401d
