Jim Cromie wrote:
John E. Malmberg wrote:
The patch that I submitted is needed to eliminate a data corruption
issue that should be affecting more than just VMS.
If I have diagnosed this wrong, please let me know.
just a wild conjecture from the peanut gallery. There are some pretty
subtle tricks played in the memory allocation areas, which might
explain why nobodys responding; most dont understand it all deeply,
and given that tests pass so successfully, its hard to imagine
> an error of the size you suggest could be universally present.
> (or it could be august vacations, or firefighting at day jobs)
The original macro clearly does not match the structure that it is
supposed to be used to allocate space for.
Changing the macro for the size allocation to match the structure makes
the symptoms go away.
It is a possibility that the structure is declared wrong and instead of
being an array of structures, should be an array of pointers to
structures. I would have to do more research to determine if that is
the case.
There can be many reasons why this data corruption is not more visible.
When memory is allocated, sometimes gaps in what is in use appear.
I could only reproduce this problem by running the test script that was
failing, and any attempt to simplify the problem made the corruption go
away.
What I find is interesting is next to the macro that I changed to match
the structure, there is an alternate macro that over-allocates the data
because it claims it is compensating for broken malloc() routines on
some system. I suspect that it is not the malloc() that was broken.
-John
wb8tyw@xxxxxxx
Personal Opinion Only
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