check fails on Fedora 23

Hi

I am testing PostgreSQL (master) on Fedora 23. The query

ELECT p1.oid, p1.proname, p2.oid, p2.proname
FROM pg_proc AS p1, pg_proc AS p2
WHERE p1.oid < p2.oid AND
p1.prosrc = p2.prosrc AND
p1.prolang = 12 AND p2.prolang = 12 AND
(p1.proisagg = false OR p2.proisagg = false) AND
(p1.prolang != p2.prolang OR
p1.proisagg != p2.proisagg OR
p1.prosecdef != p2.prosecdef OR
p1.proleakproof != p2.proleakproof OR
p1.proisstrict != p2.proisstrict OR
p1.proretset != p2.proretset OR
p1.provolatile != p2.provolatile OR
p1.pronargs != p2.pronargs);

fails on assert

Program terminated with signal SIGABRT, Aborted.
#0 0x00007f3e1dfe5a98 in __GI_raise (sig=sig(at)entry=6) at
../sysdeps/unix/sysv/linux/raise.c:55
55 return INLINE_SYSCALL (tgkill, 3, pid, selftid, sig);
(gdb) bt
#0 0x00007f3e1dfe5a98 in __GI_raise (sig=sig(at)entry=6) at
../sysdeps/unix/sysv/linux/raise.c:55
#1 0x00007f3e1dfe769a in __GI_abort () at abort.c:89
#2 0x00000000007c5401 in ExceptionalCondition
(conditionName=conditionName(at)entry=0x935157 "!(compareResult < 0)",
errorType=errorType(at)entry=0x802217 "FailedAssertion",
fileName=fileName(at)entry=0x935147 "nodeMergejoin.c",
lineNumber=lineNumber(at)entry=942) at assert.c:54
#3 0x00000000005eba9f in ExecMergeJoin (node=node(at)entry=0x175f120) at
nodeMergejoin.c:942
#4 0x00000000005d3958 in ExecProcNode (node=node(at)entry=0x175f120) at
execProcnode.c:480
#5 0x00000000005cfe87 in ExecutePlan (dest=0x177d1e0, direction=<optimized
out>, numberTuples=0, sendTuples=<optimized out>,
operation=CMD_SELECT, planstate=0x175f120, estate=0x175f008) at
execMain.c:1562
#6 standard_ExecutorRun (queryDesc=0x16c7e88, direction=<optimized out>,
count=0) at execMain.c:342
#7 0x00000000006dd038 in PortalRunSelect (portal=portal(at)entry=0x16bed38,
forward=forward(at)entry=1 '\001', count=0,
count(at)entry=9223372036854775807, dest=dest(at)entry=0x177d1e0) at
pquery.c:942
#8 0x00000000006de57e in PortalRun (portal=portal(at)entry=0x16bed38,
count=count(at)entry=9223372036854775807,
isTopLevel=isTopLevel(at)entry=1 '\001', dest=dest(at)entry=0x177d1e0,
altdest=altdest(at)entry=0x177d1e0,
completionTag=completionTag(at)entry=0x7ffe4f8236f0 "") at pquery.c:786
#9 0x00000000006db29b in exec_simple_query (
query_string=0x1715318 "SELECT p1.oid, p1.proname, p2.oid,
p2.proname\nFROM pg_proc AS p1, pg_proc AS p2\nWHERE p1.oid < p2.oid
AND\n p1.prosrc = p2.prosrc AND\n p1.prolang = 12 AND p2.prolang = 12
AND\n (p1.proisagg = f"...) at postgres.c:1105
#10 PostgresMain (argc=<optimized out>, argv=argv(at)entry=0x16a57a0,
dbname=0x16a5500 "regression", username=<optimized out>)
at postgres.c:4033
#11 0x000000000046810f in BackendRun (port=0x16c5f50) at postmaster.c:4204
#12 BackendStartup (port=0x16c5f50) at postmaster.c:3880
#13 ServerLoop () at postmaster.c:1683
#14 0x000000000067e98b in PostmasterMain (argc=argc(at)entry=8,
argv=argv(at)entry=0x16a45e0)
at postmaster.c:1292
#15 0x0000000000469376 in main (argc=8, argv=0x16a45e0) at main.c:223

Linux yen 4.2.1-300.fc23.x86_64+debug #1 SMP Mon Sep 21 21:58:30 UTC 2015
x86_64 x86_64 x86_64 GNU/Linux
gcc (GCC) 5.1.1 20150618 (Red Hat 5.1.1-4)

Postgres 9.4.4 is working well

Regards

Pavel