Is line 7 (now commented out) what you referred to?

#!C:/perl/bin
use warnings;
use strict;

BEGIN {
    local $@;
    # call_undefined_subroutine_or_another_error("argument");
}
print "blabla\n";
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 Error Indicators
   The variables $@, $!, $^E, and $? contain information about different
   types of error conditions that may appear during execution of a Perl
   program. The variables are shown ordered by the "distance" between the
   subsystem which reported the error and the Perl process. They correspond
   to errors detected by the Perl interpreter, C library, operating system,
   or an external program, respectively.

   To illustrate the differences between these variables, consider the
   following Perl expression, which uses a single-quoted string:

       eval q{
           open my $pipe, "/cdrom/install |" or die $!;
           my @res = <$pipe>;
           close $pipe or die "bad pipe: $?, $!";
       };

   After execution of this statement all 4 variables may have been set.

   $@ is set if the string to be "eval"-ed did not compile (this may happen
   if "open" or "close" were imported with bad prototypes), or if Perl code
   executed during evaluation die()d . In these cases the value of $@ is
   the compile error, or the argument to "die" (which will interpolate $!
   and $?). (See also Fatal, though.)