------- Additional Comments From pinskia at physics dot uc dot edu 2005-08-05
01:35 -------
Subject: Re: New: Invalid %sil register chosen when dereferenced pointer used
in inline asm with -O0
On Aug 4, 2005, at 8:32 PM, ianw at gelato dot unsw dot edu dot au
wrote:
> /* this one doesn't */
> __asm__ __volatile__("xchgb %0, %1"
> : "=r"(old), "=m"(*newp)
> : "0"(0xff), "m"(*newp) : "memory");
This is not a bug.
r is selecting %sil which is a valid register for x86_64.
"r" is assuming that it is a full size register.
Use "Q" instead.
-- Pinski
PS The reason why I am CC you instead of writing this into bugzilla is
because
bugzilla seems dead.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23242
