lkml.org 
[lkml]   [2007]   [Jul]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: sparse breakage (x86_64: Add vDSO for x86-64 with gettimeofday/clock_gettime/getcpu)
On Sun, Jul 22, 2007 at 06:06:57PM +0100, Al Viro wrote:
> On Sun, Jul 22, 2007 at 08:08:09PM +0400, Alexey Dobriyan wrote:
> > Andi, with new vDSO code sparse fails to check with usual invocation here:
>
> Fucks with CF and not in a good way...
>
> CF := $(PROFILING) -mcmodel=small -fPIC -g0 -O2 -fasynchronous-unwind-tables -m64
>
> $(obj)/vclock_gettime.o: CFLAGS = $(CF)
> $(obj)/vgetcpu.o: CFLAGS = $(CF)
>
> s/CF/CCF/ in there (arch/x86_64/vdso/Makefile) fixes gcc problems; sparse
> ones remain and I'll look into that when I get some sleep (26 hours uptime
> right now). I think I have a good idea of what's going on there, but
> I'd rather not touch that code until tonight.
>
> For now just rename the variable in makefile (obviously the right thing
> to do) and that will give you sparse runs not aborted at that point.

Actually,

ed evaluate.c <<EOF
/evaluate_member_dereference
/examine_symbol_type/m/ctype =
w
q
EOF

ought to take care of sparse, AFAICS. IOW, in evaluate_member_dereference()
we need to do examine_symbol_type(ctype) before checking ctype->type, etc.
As it is, we end up with SYM_TYPEOF node there and it's not expanded until
we'd checked if we have SYM_STRUCT. We would, after expansion, but we don't
do it until too late.

I haven't checked if that's causes any regressions, but it looks
straightforward enough to be a plausible fix. I won't test it until
tonight, though (see above). Minimal testcase is
struct foo {int x;} v;
typeof(v) *p;
void bar(void)
{
p->x = 0;
}
and any serious regression testing should get both the sparse tests and
comparing kernel builds with and without that fix...
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-07-22 19:31    [W:0.056 / U:0.056 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site