[lazarus] Progressbar example for win32 crashes

[Micha Nelissen]

Hi,

When running the progressbar example it shows the main form, then after a
while a second form (larger than screen it seems) with two buttons, one with
a green icon and the other with a red icon, however without text. It then
segfaults. It seems the timer does not work properly, but I can't track the
source of the problem real well. If I try to trace it in gdb, then it loses
control when calling DoOnTimer in line 154 of customtimer.pas Can somebody
give me some debugging hints?

---GDB Output:---
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There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i686-pc-mingw32".
(gdb) file progressbar.exe
Reading symbols from progressbar.exe...done.
(gdb) run
Starting program: D:\Projects\freepascal\lazarus\examples/progressbar.exe

Program received signal SIGSEGV, Segmentation fault.
$00494169 in SYSWIN32 ()
(gdb) bt
#0  $00494169 in SYSWIN32 ()
#1  $0041d9b6 in TRACEASSERTHANDLER (
<a load of junk>, LINENO=0, THEADDR=40500924) at utrace.pp:63
#2  $0045616f in TIMERWINDOWPROC (WINDOW_HWND=12255580, MSG=275,
    WPARAM=5074880, LPARAM=0) at win32callback.inc:521
#3  $77e3a244 in _size_of_stack_reserve__ ()
#4  $77e145e5 in _size_of_stack_reserve__ ()
#5  $77e15b51 in _size_of_stack_reserve__ ()
#6  $00418733 in TAPPLICATION__HANDLEMESSAGE (this=$4d70e0)
    at application.inc:689
#7  $004189c8 in TAPPLICATION__RUN (this=$4d70e0) at application.inc:798
#8  $0049c2a2 in main () at progressbar.pp:278
(gdb)

---Trace output----

 [TCustomForm.LMPaint] TFORM1
> [TWinControl.WMPaint] TFORM1 Msg.DC: 0x680108C6
> [TWinControl.PaintHandler] TFORM1 --> Msg.DC: 0x680108C6
> [TWin32Object.MoveToEx] DC:0x680108C6, X:0, Y:0
< [TWin32Object.MoveToEx] DC:0x680108C6, X:0, Y:0
< [TWinControl.PaintHandler] TFORM1
< [TWinControl.WMPaint] TFORM1
WindowProc - Exit
WindowProc - Start
WindowProc - Getting Object With Callback Procedure
WindowProc - Getting Callback Object
WindowProc - Checking Proc
WindowProc - Window Value: $0180-10944896; Msg Value: WM_CTLCOLORBTN;
WParam: $0
9BF; LParam: $0164
WindowProc - Exit
WindowProc - Start
WindowProc - Getting Object With Callback Procedure
WindowProc - Getting Callback Object
WindowProc - Checking Proc
WindowProc - Window Value: $0180-10944896; Msg Value: WM_CTLCOLORBTN;
WParam: $0
9BF; LParam: $0166
WindowProc - Exit
WindowProc - Start
WindowProc - Getting Object With Callback Procedure
WindowProc - Getting Callback Object
WindowProc - Checking Proc
WindowProc - Window Value: $0180-10944896; Msg Value: WM_CTLCOLORBTN;
WParam: $0
9BF; LParam: $016A
WindowProc - Exit
WindowProc - Start
WindowProc - Getting Object With Callback Procedure
WindowProc - Getting Callback Object
WindowProc - Checking Proc
WindowProc - Window Value: $0180-10944896; Msg Value: WM_CTLCOLORBTN;
WParam: $0
9BF; LParam: $0182
WindowProc - Exit
WindowProc - Start
WindowProc - Getting Object With Callback Procedure
WindowProc - Getting Callback Object
WindowProc - Checking Proc
WindowProc - Window Value: $0180-10944896; Msg Value: WM_CTLCOLORBTN;
WParam: $0
9BF; LParam: $01D8
WindowProc - Exit
WindowProc - Start
WindowProc - Getting Object With Callback Procedure
WindowProc - Getting Callback Object
WindowProc - Checking Proc
WindowProc - Window Value: $0180-10944896; Msg Value: WM_CTLCOLORBTN;
WParam: $0
9BF; LParam: $0262
WindowProc - Exit
WindowProc - Start
WindowProc - Getting Object With Callback Procedure
WindowProc - Getting Callback Object
WindowProc - Checking Proc
WindowProc - Window Value: $0180-10944896; Msg Value: WM_CTLCOLORBTN;
WParam: $0
9BF; LParam: $0290
WindowProc - Exit
IntSendMessage3 - Start, Received (LM_SETVALUE)
IntSendMessage3 - Value of Sender = $004D8D00
[TWin32Object.SetValue] TPROGRESSBAR
TWin32Object.WaitMessage - Start
Leave wait message

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

Regards,

Micha.