Something like this will do it (note the "-w" which I suppose you are using too):

#!/usr/bin/perl -w
use CGI;

CGI->STORE ('foo', undef);

[download]

So you can trigger this by passing an undefined parameter value to STORE() but only with "-w". Use warnings instead if you don't want to see it.

In reply to Re: Perl CGI.PM: Use of uninitialized value $vals by hippo
in thread Perl CGI.PM: Use of uninitialized value $vals by Anonymous Monk

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