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POTrack down stack trace that created object in Windbg
 

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    <p>I'm trying to track down a memory leak in a C++ application in Windows and I've got a memory dump of the application with a large number of leaked objects. I'm using Windbg to track them down by doing the following:</p> <pre><code>// Get heap stats !heap -s </code></pre> <p>This shows the following:</p> <pre><code> Heap Flags Reserv Commit Virt Free List UCR Virt Lock Fast (k) (k) (k) (k) length blocks cont. heap ----------------------------------------------------------------------------- 00150000 00000002 1024 272 272 20 2 1 0 0 L 00250000 00001002 64 24 24 9 1 1 0 0 L 00260000 00008000 64 12 12 10 1 1 0 0 003a0000 00001002 64 24 24 1 0 1 0 0 L 003d0000 00001002 392256 292256 292256 3 1 1 0 49 L 00bb0000 00001002 64 56 56 1 1 1 0 0 L 00c30000 00001002 64 32 32 7 1 1 0 0 L ----------------------------------------------------------------------------- </code></pre> <p>So I can see that heap 003d0000 contains the leaking objects so I use:</p> <pre><code>// Get individual heap stats !heap -stat -h 003d0000 </code></pre> <p>Which shows:</p> <pre><code>heap @ 003d0000 group-by: TOTSIZE max-display: 20 size #blocks total ( %) (percent of total busy bytes) 98 105de3 - 9b7bec8 (61.59) 50 f052f - 4b19eb0 (29.75) 8 21829f - 10c14f8 (6.64) 2a0 881 - 1652a0 (0.55) d0 a5e - 86c60 (0.21) 48 19a1 - 73548 (0.18) c0 8f0 - 6b400 (0.17) 490 155 - 613d0 (0.15) 40 1300 - 4c000 (0.12) 20 1ff1 - 3fe20 (0.10) 7c 7e1 - 3d0fc (0.09) 28 120c - 2d1e0 (0.07) 8708 5 - 2a328 (0.07) 34 8f4 - 1d190 (0.05) e0 1dd - 1a160 (0.04) bb88 2 - 17710 (0.04) f0 12b - 11850 (0.03) 30 45d - d170 (0.02) 10 b73 - b730 (0.02) 90 f4 - 8940 (0.01) </code></pre> <p>So I have a leak of an object 98 bytes in size, I can track down what that object is with:</p> <pre><code>!heap -flt s 98 </code></pre> <p>This shows:</p> <pre><code>&lt;snip&gt; 19f56c38 0014 0014 [01] 19f56c40 00098 - (busy) MyApp!MyObject::`vftable' &lt;snip&gt; </code></pre> <p>This is where my knowledge of Windbg runs out, I can see that the object on the heap is of class <code>MyObject</code> but how do I find out where this object was created?</p> <p>Any help would be very much appreciated!</p> <p>Thanks, J</p>
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