I've got ver 3.20 and lines 827 thru 831 are

       eval "package $pack; $code";
       if ($@) {
       $@ =~ s/ at .*\n//;
       croak("$AUTOLOAD: $@");
       }
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this is in sub _compile.

If the content_type is as set by the FORM tag in the sample HTML file, the the content_type that comes through in the environment variable is multipart/form-data; boundary=---------------------------24805226817341 and the behavior is as I described with either the pattern match error or infininte wait if I debug. If I delete that parameter from the FORM statement the content_type is application/x-www-form-urlencoded and I get the infinite wait whether I run straight through or debug.