[GNC] Crash with no information when using custom F::Q module

[Derek Robinson]

New to the list - please direct me to previous posts if I've missed something that will explain what's happening.
I wrote a custom F::Q module to extract daily "prices" from Vanguard 529 plan portfolios that are not traded on exchanges. I believe I've done that correctly. When I run gnc-fq-dump, I get return values that make sense and appear to be the same returns I would get from using an existing module (say yahoo_json) to query for a traded security (say CSCO). However, when I configure one of my securities in Gnucash (build 3.7+, F::Q version 1.49) the program crashes. There is no log output in gnucash.trace.xxxxxx.log (the file exists, but it's blank) and no useful information from gdb. I may have installed gdb incorrectly, or maybe I'm using it incorrectly. All I get is "Inferior 1 (process xxxx) exited with code 01" and "No stack" after using bt.
I'd appreciate any guidance an experienced user can provide. Thanks!
Derek

F::Q module code

package Finance::Quote::VanguardPortfolios529;
require 5.005;
our $VERSION = '1.49'; # VERSION
use strict;use HTTP::Request::Common;use HTML::TableExtract;use HTML::TreeBuilder;use Text::Template;use Encode qw(decode);use Time::Piece;
sub methods {   return ( vanguardportfolios529   => \&vanguardportfolios529 );}
my @labels = qw/date isodate nav/;sub labels {  return ( iexcloud => \@labels, );}
sub vanguardportfolios529 {    my $quoter = shift;    my @portfolios = @_;        my (%info, $symbol, $url, $reply, $code, $desc, $body);    my $ua = $quoter->user_agent();        my $quantity = @portfolios;
    foreach my $symbol (@portfolios) {  my $t = localtime; my $t2 = $t - 7*86400; my $URL = Text::Template->new(TYPE => 'STRING', SOURCE => 'https://personal.vanguard.com/us/funds/tools/pricehistorysearch?radio=1&results=get&FundType=529Plans&FundIntExt=INT&FundId={$symbol}&fundName={$symbol}&radiobutton2=1&beginDate='.$t2->mon.'%2F'.$t2->mday.'%2F'.$t2->year.'&endDate='.$t->mon.'%2F'.$t->mday.'%2F'.$t->year.'&year=#res'); # Vanguard price history doesn't like invalid dates, so we pass a date range from a week ago through today - this range will always return SOME valid data, unless markets close for several days.         # Get the web page        $url   = $URL->fill_in(HASH => {symbol => $symbol});        $reply = $ua->request( GET $url);        $code  = $reply->code;        $desc  = HTTP::Status::status_message($code);        $body  = decode('UTF-8', $reply->content);         if ($code != 200) {            $info{ $symbol, 'success' } = 0;            $info{ $symbol, 'errormsg' } = $desc;            next;        }  # Extract first table.  my $te = HTML::TableExtract->new( headers => [qw(Date Price)] );        $te->parse($body);
 my $ts = $te->first_table_found();  # It's a simple table - just dates and prices. my $currprice; my $currdate;  # Iterate over table. We will end up passing the last row (most current price) to the constructor below. foreach my $row ($ts->rows) { $currprice = @$row[1]; $currdate = @$row[0]; }         eval { $info{$symbol, 'symbol'}             = $symbol; $info{$symbol, 'method'}             = 'vanguardportfolios529'; $info{$symbol, 'nav'}                = $currprice =~ s/[\$,]//g ? $currprice : die('failed to parse last price'); $info{$symbol, 'currency'}           = 'USD'; $info{$symbol, 'success'}            = 1; $quoter->store_date( \%info, $symbol, { usdate => $currdate } ); } or do { $info{$symbol, 'errormsg'} = $@; $info{$symbol, 'success'}  = 0;        }  }
    return wantarray() ? %info : \%info;}
1;

gnc-fq-dump output
C:\Program Files (x86)\gnucash\bin>perl gnc-fq-dump vanguardportfolios529 4517Finance::Quote fields Gnucash uses:    symbol: 4517                 <=== required      date: 11/15/2019           <=== recommended  currency: USD                  <=== required      last:                      <=\       nav: 51.22                <=== one of these     price:                      <=/  timezone:                      <=== optional
C:\Program Files (x86)\gnucash\bin>