pplies to:Oracle Server - Enterprise Edition - Version: 10.2.0.4
Information in this document applies to any platform.
When attempting to make a select statement
the following error occurs.
Exception signal: 11 (SIGSEGV), code: 1 (Address not mapped to object), addr: 0x78, PC: [0x101e4a500, koksspac()+352]
ksedmp: internal or fatal error
ORA-07445: exception encountered: core dump [koksspac()+352] [SIGSEGV] [Address not mapped to object] [0x000000078]  
You may see some or all of the following function codes in the 'Call Stack Trace' section of the trace file:
koksspac qcsjaxsl qcsjgcn qcscif qcsrctq qcssrc qcsrcr qcsrnr qcsridn qcsraic qcspqb qcsevw kkmevw kkmfcbvw kkmfcblo kkmpfcbk qcsprfro qcscpfro_chn qcscpqbc qcsjcfro qcsjanti qcsjfull qcsfpaj qcsprfro qcsprfro_tree qcsprfro_tree qcspafq qcspqb kkmdrv opiSem opiDeferredSem opitca kksFullTypeCheck rpiswu2 kksLoadChild kxsGetRuntimeLock kksfbc kkspsc0 kksParseCursor opiosq0 kpooprx kpoal8 opiodr ttcpip opitsk opiino opiodr opidrv sou2o opimai_real main start
This is caused by:
Bug: 5368296 : SQL NOT GENERATING ORA-00918 WHEN USING JOIN
1 - Upgrade to 11.1 or higher
2- Apply patch: 5368296
3. Apply the workaround : Resolve the ambiguity by adding the table_name before the column name.
SQL query involving joins errors out with :
ORA-07445: exception encountered: core dump [koksspac()+264] [SIGSEGV] [ADDR:0x80] [PC:0x7B57F80] [Address not mapped to object] 
The error usually happens when there are columns ambiguously defined where there are more than one table involved in the query having columns with same name.
In normal circumstances you would get an error like: ORA-918: column ambiguously defined.
i.e. select <table_name>.<column_name>, ...