[fpc-pascal] self corrupted after jump to overridden method

[Mattias Gaertner]

Hi,

I have a strange bug, that suddenly Self becomes a random value when
calling an overridden virtual method. It happens when activating a
TCustomSQLQuery.
Below is a gdb stacktrace with fpc 3.3.1, where Self became 0. On other
runs I saw various other values.

Where to start looking?
It happens in Lazarus at designtime, so maybe some vmt issue?


#0  0x00000000013cba40 in INTERNALOPEN (this=0x0) at
fcl-db/src/sqldb/sqldb.pp:3140 

#1  0x0000000001250f1d in DOINTERNALOPEN
(this=0x7fffffffc5c0) at fcl-db/src/base/dataset.inc:410 

#2
0x00000000012520f1 in OPENCURSOR (this=0x7ffff52aab50, INFOQUERY=184)
at fcl-db/src/base/dataset.inc:958 

#3  0x00000000013cac53 in OPENCURSOR
(this=0x7ffff52aab50, INFOQUERY=false) at
fcl-db/src/sqldb/sqldb.pp:2824 

#4  0x0000000001252518 in SETACTIVE
(this=0x7ffff52aab50, VALUE=true) at fcl-db/src/base/dataset.inc:1093

#5  0x000000000057a662 in SETORDPROP (INSTANCE=0x7fffffffd001,
PROPINFO=0x7ffff52aab50, VALUE=1) at ../objpas/typinfo.pp:1898 

#6
0x0000000000a7a239 in SETORDVALUE (this=0x7fffc47155e0, NEWVALUE=1) at
propedits.pp:3315


Mattias