codlin_month is up and complain - PL/Python crash

I revived codlin_month and it falls during PL/Python test:

http://www.pgbuildfarm.org/cgi-bin/show_log.pl?nm=codlin_moth&dt=2010-02-16%2015:09:05

TRAP: BadArgument("!(((context) != 0 && (((((Node*)((context)))->type)
== T_AllocSetContext))))", File: "mcxt.c", Line: 641)

feaf5005 _lwp_kill (1, 6, 80459c8, fea9bbde) + 15
fea9bbea raise (6, 0, 8045a18, fea725aa) + 22
fea725ca abort (8046670, 8361f80, 8045a48, 8719ccf, 89021f0,
89021e4) + f2
086d07c0 ExceptionalCondition (89021f0, 89021e4, 89021dc, 281) + 58
08719ccf MemoryContextSwitchTo (89264ac, 0, 0, 8045a7c) + 47
fec21990 PLy_spi_execute (0, 8b141cc, 80460f8, fe84abde) + 750
fe84ad6e PyCFunction_Call (8b0ff6c, 8b141cc, 0, fe8a8d92) + 19e
fe8a91a0 call_function (80461bc, 1, 610f2d31, fe8a3206) + 41c
fe8a6221 PyEval_EvalFrameEx (8b5798c, 0, 8b0cbdc, 0) + 3029
fe8a9310 fast_function (8b05144, 80462fc, 0, 0, 0, fe91c63c) + 108
fe8a8e72 call_function (80462fc, 0, 80462d8, fe8a3206) + ee
fe8a6221 PyEval_EvalFrameEx (8b576a4, 0, 8b0cbdc, 8b0cbdc) + 3029
fe8a7cd0 PyEval_EvalCodeEx (8ab4770, 8b0cbdc, 8b0cbdc, 0, 0, 0) + 91c
fe8a3102 PyEval_EvalCode (8ab4770, 8b0cbdc, 8b0cbdc, fec17831) + 32
fec1799c PLy_function_handler (8046980, 8b5d508, 8046880, fec1480f) + 17c
fec14b92 plpython_call_handler (8046980, 8046bb0, 8046be8, 8323774) + 3aa
08324393 ExecEvalFunc (8a033b0, 8a0329c, 8a0390c, 8a039b8) + e33
0832b1bc ExecProject (8a03920, 8046c6c, 2, 8977abc) + 834
08348785 ExecResult (8a03210, 8a03184, 0, 1) + 9d
0831f66f ExecProcNode (8a03210, 1, 8a037ec, 8731314) + 227
0831a186 ExecutorRun (8a02d7c, 1, 0, 8719ad4) + 2de
084d7778 PortalRun (898effc, 7fffffff, 1, 8977b38, 8977b38) + 450
084ceae9 exec_simple_query (8976984, 0, 80473b8, 84d5185) + ba9
084d51a2 PostgresMain (2, 8973b4c, 897398c, 893d00c, 893d008,
130d7661) + 7fa
0844aded BackendRun (898c3d0) + 1cd
084440f3 ServerLoop (1, 89561d4, 3, fea7bb7e, 5c54, feb83cd8) + 973
08443004 PostmasterMain (3) + 119c
0837db12 main (3, 8047b14, 8047b24, 80fa21f) + 1ea
080fa27d _start (3, 8047be8, 8047fb0, 8047fb0, 0, 8047c35) + 7d

It seems that problem is with compiler aggressive optimization. I change
it to lower level and now it works fine. Interesting is that
MemoryContext corruption only appears with PL/Python.

Zdenek