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copied!<p><s>I'm a bit concerned that the code generated for <code>if (wsdHooks.xBenignBegin)</code> isn't very general. It assumes the only true value is <code>1</code> whereas it should really be testing for <em>any</em> nonzero value. Still, MSVC is sometimes baffling that way. It is probably nothing.</s> Never mind: these instructions are for <code>C</code> code not presented.</p> <p>Given that the eflag <code>Z</code> bit is clear and <code>EAX</code> is zero, the code did not get here by executing the instruction</p> <pre><code>719f9fa7 test eax,eax </code></pre> <p>There must be a jump from somewhere else to the instruction following (<code>719f9fa9 je SQLite_Interop!pcache1Fetch+0x2d</code>) or even the <code>call</code> instruction itself.</p> <p>Another complication is that with the x86 family, it is common for an invalid jump target (like the second byte of the <code>JE</code> instruction) to execute unperturbed (no faults) for quite a few instructions, often eventually getting back on the proper instruction alignment. Said another way, you may not be looking for a jump to the beginning of any of these instructions: a jump might be in the midst of their bytes, resulting in executing unremarkable operations like <code>add [al+ebp],al</code> which tend not to be noticed.</p> <p>I predict that a breakpoint at the <code>test</code> instruction will not be hit for the exception. The only ways to find such causes is either to be very lucky, or to suspect everything and prove them innocent one-by-one.</p>

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