data corruption

[Walter Bright]

Ellery Newcomer wrote:
> I've got this screwy problem with my old version of dmdz.
> 
> One of the functions runs through a loop that appends to a string[] 
> about four or five times. When it's chewing through a large amount of 
> source code, maybe 1 call out of 200 the third element of the array gets 
> corrupted just after an append.
> 
> duping the string that gets appended has no effect.
> 
> Trying to print out the pointer addresses to the strings does seem to 
> get rid of the problem.
> 
> I'm using dmd 2.042; it doesn't seem to happen on 2.040

If you can turn this into a standalone reproducible test case, please do so and 
put it on bugzilla. Memory corruption problems are the worst, so doing this 
would be a big help.