On Thu, 11 Jan 2018, Peter Zijlstra wrote:
> > I think I heard that retpolines won't be ported to anything older than
> > GCC 4.9, so maybe it's safe to use '%='. I don't remember when it was
> > introduced into GCC though.
>
> root@interlagos:~/tmp# gcc-4.8 -o test test.c
> root@interlagos:~/tmp# ./test
> 11
>
> --- test.c
>
> #include <stdio.h>
>
> void main(void)
> {
> int val;
>
> asm ("mov $(%=),%0" : "=A" (val));
>
> printf("%d\n", val);
> }
# gcc --version
gcc (SUSE Linux) 4.3.4 [gcc-4_3-branch revision 152973]
# ./test
8
So this part is OK. The asm-goto hard dependency would be worse with that
compiler though.
--
Jiri Kosina
SUSE Labs
