https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54450
--- Comment #7 from Georg-Johann Lay <gjl at gcc dot gnu.org> --- (In reply to Eric Gallager from comment #6) > (In reply to Marek Polacek from comment #2) > > Probably dup of http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41045 > > Agreed, closing as a duplicate of it > > *** This bug has been marked as a duplicate of bug 41045 *** Really? What the OP wants is >> void *ptr; >> >> __asm__ ("my_function:\n\t" >> "jmp *%0\n\t" : : "r"(ptr)); Constraint "r" cannot work at toplevel, hence this PR is invalid. What PR41045 is about is top-level asm arguments that are compiler-time constants (constraint "n") and maybe also symbols (constraints "i" and "s"). So the initial request is only valid if the address of ptr was used (and &ptr is CONST_INT, CONST or SYMBOL_REF etc.): void *ptr; __asm__ ("my_function:\n\t" "jmp ??? %0" : : "i" (&ptr));