[sqlsmith] Failed assertion in BecomeLockGroupLeader - Mailing list pgsql-hackers

Hi,

tonight's sqlsmith run yielded another core dump:

TRAP: FailedAssertion("!(MyProc->lockGroupLeader == ((void *)0))", File: "proc.c", Line: 1787)

I couldn't identifiy a query for it though: debug_query_string is empty.
Additionally, the offending query was not reported in the error context
as it typically is for non-parallel executor crashes.

regards,
Andreas

GNU gdb (Debian 7.7.1+dfsg-5) 7.7.1
Core was generated by `postgres: bgworker: parallel worker for PID 4706                 '.
Program terminated with signal SIGABRT, Aborted.
#0  0x00007ff1bda16067 in __GI_raise (sig=sig@entry=6)   at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
56    ../nptl/sysdeps/unix/sysv/linux/raise.c: Datei oder Verzeichnis nicht gefunden.
#0  0x00007ff1bda16067 in __GI_raise (sig=sig@entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
#1  0x00007ff1bda17448 in __GI_abort () at abort.c:89
#2  0x00000000007eaa11 in ExceptionalCondition (conditionName=conditionName@entry=0x988318 "!(MyProc->lockGroupLeader
==((void *)0))", errorType=errorType@entry=0x82a45d "FailedAssertion", fileName=fileName@entry=0x8760e5 "proc.c",
lineNumber=lineNumber@entry=1787)at assert.c:54
 
#3  0x00000000006e3e7b in BecomeLockGroupLeader () at proc.c:1787
#4  0x00000000004e6a59 in LaunchParallelWorkers (pcxt=pcxt@entry=0x1db05c8) at parallel.c:437
#5  0x00000000005ef2d7 in ExecGather (node=node@entry=0x1d9d0b8) at nodeGather.c:168
#6  0x00000000005dd788 in ExecProcNode (node=node@entry=0x1d9d0b8) at execProcnode.c:515
#7  0x00000000005d999f in ExecutePlan (dest=0x1d7d310, direction=<optimized out>, numberTuples=0, sendTuples=<optimized
out>,operation=CMD_SELECT, use_parallel_mode=<optimized out>, planstate=0x1d9d0b8, estate=0x1d9c858) at
execMain.c:1567
#8  standard_ExecutorRun (queryDesc=0x1db0080, direction=<optimized out>, count=0) at execMain.c:338
#9  0x00000000005dcb3f in ParallelQueryMain (seg=<optimized out>, toc=0x7ff1be507000) at execParallel.c:716
#10 0x00000000004e608b in ParallelWorkerMain (main_arg=<optimized out>) at parallel.c:1033
#11 0x0000000000683a42 in StartBackgroundWorker () at bgworker.c:726
#12 0x000000000068eb82 in do_start_bgworker (rw=0x1d24ec0) at postmaster.c:5531
#13 maybe_start_bgworker () at postmaster.c:5706
#14 0x000000000046c993 in ServerLoop () at postmaster.c:1762
#15 0x00000000006909fe in PostmasterMain (argc=argc@entry=3, argv=argv@entry=0x1cfa560) at postmaster.c:1298
#16 0x000000000046d5ed in main (argc=3, argv=0x1cfa560) at main.c:228
(gdb) bt full
#3  0x00000000006e3e7b in BecomeLockGroupLeader () at proc.c:1787       leader_lwlock = <optimized out>
#4  0x00000000004e6a59 in LaunchParallelWorkers (pcxt=pcxt@entry=0x1db05c8) at parallel.c:437       oldcontext =
0x1d9ced0      worker = {         bgw_name =
"\220\a\333\001\000\000\000\000\370\340L\276\361\177\000\000\370\373\025\264\361\177\000\000P\a\333\001\000\000\000\000X\310\331\001\000\000\000\000\004\000\000\000\000\000\000\000\310\005\333\001\000\000\000\000\233\222J\000\000\000\000",
        bgw_flags = 1,          bgw_start_time = BgWorkerStart_PostmasterStart,          bgw_restart_time = 1,
bgw_main= 0x0,          bgw_library_name =
"\000\000\000\000\000\000\000\000\001\000\000\000\000\000\000\000u\222J\000\000\000\000\000\350\336\331\001\000\000\000\000\360\260a\000\000\000\000\000\200\315]\000\000\000\000\000\300\330\367\217\375\177\000\000h\205\333\001\000\000\000",
        bgw_function_name =
"`\346\327\001\000\000\000\000\004\000\000\000\000\000\000\000\360\260a\000\000\000\000\000\200\315]\000\000\000\000\000\300\330\367\217\375\177\000\000h\317\331\001\000\000\000\000\210\325\327\001\000\000\000\000\004\000\000\000\000\000\000",
        bgw_main_arg = 6402288,          bgw_extra =
"X\310\331\001\000\000\000\000\000\000\000\000\000\000\000\000\060\233\333\001\000\000\000\000\001\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000l\321]\000\000\000\000\000\000\000\000\000\000\000\000\000H-\334\001\000\000\000\000h\317\331\001\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\274\341M\276\361\177\000\000\310\005\333\001\000\000\000\000\004\000\000\000\000\000\000\000\310\005\333\001\000\000\000\000\000\000\000\000\000\000\000",
        bgw_notify_pid = 4       }       i = <optimized out>       any_registrations_failed = 0 '\000'
 
#5  0x00000000005ef2d7 in ExecGather (node=node@entry=0x1d9d0b8) at nodeGather.c:168       pcxt = 0x1db05c8
estate= <optimized out>       gather = 0x1d7d440       fslot = 0x1d9ced0       i = <optimized out>       resultSlot =
<optimizedout>       isDone = ExprSingleResult       econtext = <optimized out>
 
#6  0x00000000005dd788 in ExecProcNode (node=node@entry=0x1d9d0b8) at execProcnode.c:515       result = <optimized out>
     __func__ = "ExecProcNode"
 
#7  0x00000000005d999f in ExecutePlan (dest=0x1d7d310, direction=<optimized out>, numberTuples=0, sendTuples=<optimized
out>,operation=CMD_SELECT, use_parallel_mode=<optimized out>, planstate=0x1d9d0b8, estate=0x1d9c858) at execMain.c:1567
     slot = <optimized out>       current_tuple_count = 0
 
#8  standard_ExecutorRun (queryDesc=0x1db0080, direction=<optimized out>, count=0) at execMain.c:338       estate =
0x1d9c858      operation = CMD_SELECT       dest = 0x1d7d310       sendTuples = <optimized out>
 
#9  0x00000000005dcb3f in ParallelQueryMain (seg=<optimized out>, toc=0x7ff1be507000) at execParallel.c:716
buffer_usage= <optimized out>       instrumentation = 0x0       instrument_options = 0
 
#10 0x00000000004e608b in ParallelWorkerMain (main_arg=<optimized out>) at parallel.c:1033       seg = 0x1d29d30
toc= 0x7ff1be507000       fps = 0x7ff1be51ec38       error_queue_space = <optimized out>       mq = <optimized out>
 mqh = <optimized out>       libraryspace = <optimized out>       gucspace = <optimized out>       combocidspace =
<optimizedout>       tsnapspace = <optimized out>       asnapspace = <optimized out>       tstatespace = <optimized
out>      msgbuf = {         data = 0x0,          len = 8,          maxlen = 1024,          cursor = 75       }
__func__= "ParallelWorkerMain"
 
#11 0x0000000000683a42 in StartBackgroundWorker () at bgworker.c:726       local_sigjmp_buf = {{           __jmpbuf =
{30559936,3179006107653964804, 140727018841376, 1461888082, 4294967295, 30560912, -3178127926870473724,
3179007261678568452},           __mask_was_saved = 1,            __saved_mask = {             __val =
{18446744066192964103,0, 0, 140727018839040, 0, 2415385408, 30532816, 140727018782720, 0, 0, 140727018840336,
18446744073709551615,0, 30514160, 140676256394695, 8589934591}           }         }}       buf = "bgworker: parallel
workerfor PID 4706\000\000\345[...]"       worker = 0x1d24ec0       entrypt = <optimized out>       __func__ =
"StartBackgroundWorker"
#12 0x000000000068eb82 in do_start_bgworker (rw=0x1d24ec0) at postmaster.c:5531       worker_pid = <optimized out>
#13 maybe_start_bgworker () at postmaster.c:5706       rw = 0x1d24ec0       iter = {         cur = 0x1d25048,
next= 0x0,          prev = 0x1d207d8       }       now = <optimized out>
 
#14 0x000000000046c993 in ServerLoop () at postmaster.c:1762       rmask = {         fds_bits = {24, 0, 0, 0, 0, 0, 0,
0,0, 0, 0, 0, 0, 0, 0, 0}       }       selres = <optimized out>       now = <optimized out>       readmask = {
fds_bits= {24, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}       }       last_lockfile_recheck_time = 1461888082
last_touch_time= 1461885050       __func__ = "ServerLoop"
 
#15 0x00000000006909fe in PostmasterMain (argc=argc@entry=3, argv=argv@entry=0x1cfa560) at postmaster.c:1298       opt
=<optimized out>       status = <optimized out>       userDoption = <optimized out>       listen_addr_saved =
<optimizedout>       i = <optimized out>       output_config_variable = <optimized out>       __func__ =
"PostmasterMain"
#16 0x000000000046d5ed in main (argc=3, argv=0x1cfa560) at main.c:228