C++ application with pro*c generating random errors

Question

Hi there,
As described, I have a C++ application with a pro*c module to access the DB. The problem is that it produces random errors.
Randomly, it fails executing a query, but other times it fails in other modules, or just opening a cursor. I list you two examples of queries that fail:
================================================================
CHECK_CONNECTED
EXEC SQL BEGIN DECLARE SECTION;
long Id_db;
long startValidityMicroseconds_db;
long stopValidityMicroseconds_db;
VARCHAR name_db [LEN_NAME + 1];
VARCHAR creationDate_db [LEN_DATE + 1];
VARCHAR startValidityDate_db [LEN_DATE + 7 + 1];
VARCHAR stopValidityDate_db [LEN_DATE + 7 + 1];
short name_db_ind;
EXEC SQL END DECLARE SECTION;
// Set the key
Id_db = Id
EXEC SQL SELECT NAME,
                         TO_CHAR(CREATION_DATE, :DATE_FORMAT),
                         TO_CHAR(START_VALIDITY_DATE, :DATE_FORMAT),
                         TO_CHAR(STOP_VALIDITY_DATE, :DATE_FORMAT),
                         NVL (START_VALIDITY_MICROSECONDS ,0),
                         NVL (STOP_VALIDITY_MICROSECONDS ,0),
INTO :name_db :name_db_ind,
     :creationDate_db,
     :startValidityDate_db,
     :stopValidityDate_db,
     :startValidityMicroseconds_db,
     :stopValidityMicroseconds_db,
FROM ROP_TB
WHERE ID = :Id_db;
================================================================
================================================================
CHECK_CONNECTED
EXEC SQL BEGIN DECLARE SECTION;
     long objectId_db;
     VARCHAR objectName_db [LEN_OBJECT_NAME + 1];
EXEC SQL END DECLARE SECTION;
strncpy ((char *) objectName_db.arr, object_db.c_str (), LEN_OBJECT_NAME);
objectName_db.len = object_db.length ();
EXEC SQL DECLARE CU_OBJECT_TB CURSOR FOR
SELECT OBJECT_ID INTO :objectId_db
FROM OBJECT_TB
WHERE OBJECT_NAME = :objectName_db;
EXEC SQL OPEN CU_OBJECT_TB;
================================================================
It keeps failing randomly and I don't know really know what my eyes are missing. Sometimes I get a "simple" seg fault because a query returned invalid values and my application crashes, other times I get oracle errors.
I really hope someone could help me here :)
Kind regards!

Answer 1

Well, random because it is not always the same nor the error code.
- Sometimes I get segmentation fault on "sqlcxt";
- "ORA-01024: invalid datatype in OCI call" on queries that usually work
- "ORA-03114: not connected to ORACLE" on queries that usually work
I have run valgrind and the only "place" where there could be an issue is reported to be caused by oracle libs:
==27055== 8,214 bytes in 1 blocks are possibly lost in loss record 193 of 206
==27055== at 0x40046FF: calloc (vg_replace_malloc.c:279)
==27055== by 0x43E2975: nsbal (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x42F04E6: nsiorini (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x4300FD2: nsopenalloc_nsntx (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x42FFD73: nsopenmplx (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x42F91FD: nsopen (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x42BDAFE: nscall1 (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x42BB0D7: nscall (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x435F653: niotns (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x43F9E40: nigcall (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x436AD4B: osncon (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)
==27055== by 0x41EAA31: kpuadef (in /home/oracle/app/oracle/product/11.1.0/db_1/lib/libclntsh.so.11.1)