Re: Curious buildfarm failures (fwd)

On 2013-01-16 02:34:52 +0100, Andres Freund wrote:
> On 2013-01-16 02:13:26 +0100, Andres Freund wrote:
> > On 2013-01-15 19:56:52 -0500, Tom Lane wrote:
> > > Andres Freund <andres@2ndquadrant.com> writes:
> > > > FWIW its also triggerable if two other function calls are places inside
> > > > the above if() (I tried fprintf(stderr, "argh") and kill(0, 0)).
> > > 
> > > [ confused... ]  You mean replacing the abort() in the elog macro with
> > > one of these functions?  Or something else?
> > 
> > I mean replacing the elog(ERROR, "ForwardFsyncRequest must...") with any
> > two function calls inside a do/while(0). I just tried to place some
> > random functions there instead of the elog to make sure its unrelated,
> > and it still triggers the problem even before the elog commit. The
> > assembler output of that function changes wildly with tiny changes and I
> > don't understand IA-64 at all (does anybody?), so I don't see anything
> > we can do there.
> > 
> > > > It seems the change just made an existing issue visible.
> > > > No idea what to do about it.
> > > 
> > > Pretty clearly a compiler bug at this point.  Since there doesn't seem
> > > to be a clean workaround (no, I don't want to expand the struct
> > > assignment manually), and anyway we can't be sure that the bug doesn't
> > > also manifest in other places, recommending Sergey update his compiler
> > > seems like the thing to do.
> > 
> > Yea. Don't have a better suggestion.
> > 
> > > At this point I'm more interested in his report in
> > > <alpine.LRH.2.03.1301152012220.773@ast.cam.ac.uk> about
> > > the Assert at spgdoinsert.c:1222 failing.  That's pretty new code, so
> > > more likely to have a genuine bug, and I wonder if it's related to
> > > the spgist issue in <50EBF992.2000704@qunar.com> ...
> > 
> > Yes, it looks more like it could be something real. There are
> > suspicously many other failing tests though (misc, with) that don't seem
> > to be related to the spgist crash.
> 
> #4  0x40000000001a6320 in doPickSplit (index=0x600000000007ff48, state=0x3, current=0x60000ffffff7a700, parent=0x4,
newLeafTuple=0x6,
 
>     level=512360, isNulls=64 '@', isNew=12 '\f') at spgdoinsert.c:1222
> (gdb) p parent
> $4 = {blkno = 1, buffer = 356, page = 0x200000000148eea0 "", offnum = 1, node = 4}
> 
> (gdb) p &parent
> $7 = (SPPageDesc *) 0x60000ffffff7a900

-O0 passes

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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