Re: Current tools for finding memory overwrites

In message <1170061975.577620.64890@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, asperamanca@xxxxxxxxx writes
Thanks for the info. I already downloaded a trial version and gave it
a try, but either there's nothing to be found (where I expect it), or
it might have trouble with a VB6-built application, or (most likely) I
don't yet understand the configuration well enough.

Fair enough, the whole problem with memory corruptions is that you can only detect a corruption in the area around a memory allocation, not the allocation itself (because it may be a valid write - the only people that can detect a corruption of data in an object are the people that wrote the object, by writing a function for integrity testing and calling it at regular intervals).

That said MV has many options for detecting errors. Some of them obvious, others not so. The tutorial has quite a few pointers. Plus if you know where the data is getting knobbled, the analysis tab coupled with the Allocation History settings (disable purging) can be useful for finding references to your object that also reference parts of previously deleted objects (there is your problem, some of your code is pointing at dead objects and writing over the current objects, now you know which ones, so you can go hunting). No competing tool has functionality to allow such queries.

Stephen
--
Stephen Kellett
Object Media Limited http://www.objmedia.demon.co.uk/software.html
Computer Consultancy, Software Development
Windows C++, Java, Assembler, Performance Analysis, Troubleshooting
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