[fpc-devel] heaptrc: error in linked list of heap_mem_info

[Tom Verhoeff]

When I use HeapTrc on a small program (FPC 2.2.0 on Linux; FPC 2.0.4 on
Mac OS X) and set

  QuickTrace := False
  KeepReleased := True

this results in a long list of

error in linked list of heap_mem_info
error in linked list of heap_mem_info
...

When either QuickTrace or KeepReleased is kept at its default value,
this does not happen.

It also heappens in the heaptrace example program:

Program heapex;

{ Program used to demonstrate the usage of heaptrc unit }

Uses heaptrc;

Var P1 : ^Longint;
    P2 : Pointer;
    I : longint;

begin
  QuickTrace := False; // ADDED
  KeepReleased := True; // ADDED
  SetHeapTraceOutput('heaptrc.out'); // ADDED
  New(P1);
  // causes previous allocation not to be de-allocated
  New(P1);
  Dispose(P1);
  For I:=1 to 10 do
    begin
      GetMem (P2,128);
      // When I is even, deallocate block. We loose 5 times 128
      // bytes this way.
      If (I mod 2) = 0 Then FreeMem(P2,128);
    end;
  GetMem(P2,128);
  // This will provoke an error and a memory dump
  Freemem (P2,64);
end.

Any suggestions?  Or is this combination asking for trouble
(in which case it would be good to mention this in the documentation)?

Thanks,

	Tom
-- 
E-MAIL: T.Verhoeff @ TUE.NL     | Dept. of Math. & Comp. Science
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