On 06/09/2016 10:45 AM, Jakub Jelinek wrote:
On Thu, Jun 09, 2016 at 06:43:04PM +0200, Jakub Jelinek wrote:
Yes, I'm all in favor in disabling X constraint for inline asm.
Especially if people actually try to print it as well, rather than make it
unused. That is a sure path to ICEs.
Though, on the other side, even our documentation mentions
asm volatile ("mtfsf 255,%1" : "=X"(sum): "f"(fpenv));
So perhaps we need to error just in case such an argument is printed?
Are you thinking to scan the output string for %<N> for the appropriate
<N>? That shouldn't be too hard. But that's not sufficient to address
the problem Bernd is trying to tackle AFAICT.
Jeff
