I'm using
use diagnostics
and very occasionally I get a
Use of uninitialized value in hash dereference at ....
message.

Basically, I have a background task that is accumulating information into a hash. This hash is then transacted back to the parent.
I'm using Data::Dumper to convert the hash in the background task into a string.
Once this string is received (by the parent), I then convert the string back into a hash with:
my %info   = %{ eval $dumper };
And it is this line that generates the "uninitialized value" message.
(The background task sends data back to the parent every 10 seconds, and the "uninitialized warning" message is only genereted once in 2-3 weeks).

Before executing the line above, I do check that $dumper contians $VAR1=.
I'm struggling to find out what it is about the original hash that is being packed by Data::Dumper that might cause this "uninitialized value" message.
One line of inquiry might be to see if I can get PERL to break-point when this "uninitialized value" message occurs ...
... at least then I could inspect the value of $dumper at the point of failure.

Any thoughts on how I might track down this intermittent error would be greatly appreciated.
Thank you.

In reply to Help requested to find the cause of an "uninitialized value" message by andyok

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