[Bug c/121235] Local register variable constraints aren't respected in extended asm

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121235

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |INVALID
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
```
void* inner(unsigned value) {
    unsigned t = value;
    register void* ret asm("2");
    register unsigned a0 asm("4") = t;
    __asm__ volatile("\n"

"break; %0 %1\n"

: "=r"(ret) : "r"(a0));
    return ret;
}
```

Fixes it for me.

Notice the use of a0 in inline-asm rather than value.