ODBCDatabase crashing

[E.Tejkowski <lists at sonicamigos dot com>]

I'm working on a large RB database project which was previously  
working correctly in RB5.5.5 on Mac OX 10.4.8 PPC and Intel.  With  
the upgrade to OS 10.4.9 we could no longer connect to the database  
and upgraded to RB2007. We are talking to our Sybase iAnywhere 9.02  
database via ODBC with the latest Actual Tech driver.  We also  
installed a Sybase fix for 10.0.8+.  We can now connect to the  
database but are experiencing a major crashing problem when creating  
recordsets in succession that we've narrowed down somewhat. The first  
couple of times the recordset will return the accurate number of  
records and the Move functions work correctly.  Intermittently, a  
subsequent recordset incorrectly returns only one record and the  
first MoveNext positions at EOF.  Immediately afterwards we receive  
an Unexpected Error crash.  We've built a small test project that  
repeats the problem. I'm wondering if anyone else has experience with  
this issue, and if so, if there is any sort of workaround for this?  
Below are snippets that show the code we're using when we experience  
this crash. It crashes more readily on Intel over PPC for some  
reason. Is there a bug in the ODBC plugin?

Thanks,
Erick
Intel Mac, Tiger
RB2k7r5


SNIPPET 1: The db checks out as not nil and the connection is  
successful.
--------------------------------------------------------------
   db = New ODBCDatabase
   db.DataSource =  
"dsn=somedsn;UID=someuser;PWD=somepwd;LINKS=ShMem,tcpip;DBN=" + dbName

   if db<>nil then
     MsgBox "db<>nil"
     If db.Connect() then
       msgbox "connection is successful"
     else
       msgbox "connection failed"
     end if
   else
     MsgBox "db=nil"
   end if


SNIPPET 2: We run this function for hundreds of iterations to stress  
test the code. This is where we crash. We can sometimes loop maybe  
thirty times before it crashes on Intel. Sometimes we simply get one  
record returned (when we should be getting far more).
--------------------------------------------------------------
   Dim rs as RecordSet

   If EmptyRS("SELECT Title,ArtistDisplay FROM Works" ) then
     MSgBox "No RecordSet"
     Return
   Else
     rs = db.SQLSelect("SELECT Title,ArtistDisplay FROM Works" )
     rs.MoveFirst
     Do Until rs.EOF
       Window1.ListBox1.AddRow rs.Field("Title").StringValue
       Window1.ListBox1.cell(Window1.ListBox1.LastIndex,1) = rs.Field 
("ArtistDisplay").StringValue
       rs.MoveNext
     Loop
   End if
   rs.Close


SNIPPET 3: This function returns true. Helper function for SNIPPET 2  
above.
--------------------------------------------------------------
Function EmptyRS(sql as String) As Boolean
   Dim rs as RecordSet

   rs = db.SQLSelect(sql)
   If rs = Nil  Then
     Return True
   ElseIf rs.FieldCount = 0 then
     Return true
   else
     rs.MoveFirst
     Return False
   End If
End Function



------------------------------------------------------------------

PID:    12740
Thread: 0

Exception:  EXC_BAD_ACCESS (0x0001)
Codes:      KERN_PROTECTION_FAILURE (0x0002) at 0x00000000

Thread 0 Crashed:
0   libSystem.B.dylib                 0x900031c8 strlen + 8
1   libSystem.B.dylib                 0x901302e8 _simple_vdprintf + 3688
2   libSystem.B.dylib                 0x90130b28 _simple_dprintf + 52
3   libSystem.B.dylib                 0x9012b79c malloc_printf + 132
4   libSystem.B.dylib                 0x90006ee8 szone_free + 1628
5   libtdsodbc-ppc.dylib            0x065aacc4 tds_dstr_free + 52
6   libtdsodbc-ppc.dylib            0x065874a0 desc_alloc_records + 408
7   libtdsodbc-ppc.dylib            0x06587508 desc_free_records + 72
8   libtdsodbc-ppc.dylib            0x06587714 desc_free + 28
9   libtdsodbc-ppc.dylib            0x06582c40 SQLFreeEnv + 488
10  libtdsodbc-ppc.dylib           0x06582c9c SQLFreeStmt + 20
11  atsqlsrv.so                          0x0654d064 SQLFreeHandle + 472
12  atsqlsrv.so                          0x0654cf00 SQLFreeHandle + 116
13  org.iodbc.core                    0x00fb4150 SQLFreeStmt_Internal  
+ 304
14  org.iodbc.core                    0x00fb42fc SQLFreeStmt + 260
15  ODBC Plugin 2007.rbx_0.dylib      0x00f6ae3c ODBCCloseCursor 
(dbCursor*) + 40 (odbcDatabase.cpp:2020)
16  rbframework.dylib              0x018e8a80 cursorClose + 116
17                               0x00042798 DatabaseCursor.Close%% 
o<DatabaseCursor> + 56
18                               0x007e16fc DataCtl.EmptyRS%b%s + 1136
19                               0x0027d798  
frmMainToolbar.frmMainToolbar.LoadReports%% 
o<frmMainToolbar.frmMainToolbar> + 1328
20                               0x0067fdd4  
mdiArtsystems.mdiArtsystems.hackTimer_Action%% 
o<mdiArtsystems.mdiArtsystems> + 5068
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