On Fri, Nov 15, 2013 at 4:34 AM, Uros Bizjak <ubiz...@gmail.com> wrote: > On Fri, Nov 15, 2013 at 12:35 PM, Uros Bizjak <ubiz...@gmail.com> wrote: > >>>>>>> panic: runtime error: invalid memory address or nil pointer dereference >>>>>>> [signal 0xb code=0x1 addr=0x1c] >>>>> >>>>>>> FAIL: runtime/pprof >>>>>>> gmake[2]: *** [runtime/pprof/check] Error 1 >>>>>>> >>>>>>> This one is new, I have to look into it a bit deeper. >>>>>> >>>>>> >>>>>> I don't know what is happening here. I can't recreate it. There was >>>>>> a different problem that could arise in runtime/pprof, that was fixed >>>>>> by a patch I submitted on Saturday >>>>>> (http://gcc.gnu.org/ml/gcc-patches/2013-11/msg01016.html). So it's >>>>>> possible that this is fixed now. >>>>> >>>>> The failure is specific to !USING_SPLIT_STACK targets: >>>> >>>> The same error triggered on CentOS 5.10 x86_64 (another >>>> !USING_SPLIT_STACK target) for 32bit lib (net, runtime). The panic: >>>> string is the same, only addr=0x9f. There are also a couple of >>>> segfaults (database/sql, net/http) and abort in sync/atomic. >>> >>> Could you check to see if this patch fixes the problem? Thanks. > > Oh, I was not clear. > > The patch fixes the net failure on Alpha and Centos 5.10, but other > failures on 32bit Centos 5.10 remain.
Thanks for testing it. I've committed the patch to mainline. As I noted in an earlier e-mail, the 32-bit failures are due to a general bug in the middle-end, http://gcc.gnu.org/PR59099 . That bug is causing a miscompilation of the libgo runtime code, code that is written in C. The miscompilation shows up as test failures. Ian
diff -r 9b2a1ae08a21 libgo/runtime/proc.c --- a/libgo/runtime/proc.c Thu Nov 14 14:29:49 2013 -0800 +++ b/libgo/runtime/proc.c Thu Nov 14 18:42:54 2013 -0800 @@ -1983,7 +1983,10 @@ #endif gp->gcnext_sp = nil; runtime_memclr(&gp->gcregs, sizeof gp->gcregs); - m->p->syscalltick++; + + // Don't refer to m again, we might be running on a different + // thread after returning from runtime_mcall. + runtime_m()->p->syscalltick++; } static bool
