Hello,
the Widestring Delete function in wstrings.inc accesses memory beyond the end of the string. This causes crashes after a while. The Delete function has been fixed in FPC 2.3 but the fix must be copied to the earlier branches too. I have submitted this as a bug in Mantis: http://bugs.freepascal.org/view.php?id=11365
Until it is fixed, developers can just use the fixed code below instead of the one in the System unit. You just need to find out if your platform uses FPC_WINLIKEWIDESTRING or not. On my platform, MacOS X, this is not defined.
Type
PWideRec = ^TWideRec;
TWideRec = Packed Record
{$ifdef FPC_WINLIKEWIDESTRING}
Len : DWord;
{$else FPC_WINLIKEWIDESTRING}
Ref : SizeInt;
Len : SizeInt;
{$endif FPC_WINLIKEWIDESTRING}
First : WideChar;
end;
Const
WideRecLen = SizeOf(TWideRec);
WideFirstOff = SizeOf(TWideRec)-sizeof(WideChar);
Procedure Delete (Var S : WideString; Index,Size: SizeInt); overload;
Var
LS : SizeInt;
begin
If Length(S)=0 then
exit;
if index<=0 then
exit;
LS:=PWideRec(Pointer(S)-WideFirstOff)^.Len div sizeof(WideChar);
if (Index<=LS) and (Size>0) then begin
UniqueString (S);
if Size+Index>LS then
Size:=LS-Index+1;
if Index+Size<=LS then begin
Dec(Index);
System.Move(PWideChar(S)[Index+Size],PWideChar(S)[Index],
(LS-Index-Size+1)*sizeof(WideChar));
end;
Setlength(s,LS-Size);
end;
end;Kind Regards,
Tobias Giesen
http://www.superflexible.com