Wow, Bencher::Backend has a lot of code, it's difficult to tell where $envres comes from. Unfortunately I think you'll need to boil it down to a code snippet that reproduces the problem (which still smells like a bug).

I did notice that in one place $envres comes from JSON. Here's an interesting one...

use warnings;
use strict;
use List::MoreUtils 'minmax';
use JSON::MaybeXS 'decode_json';
use Data::Dump 'dump';
my $envres = decode_json(
    q# [ [], [], [{"time":"0.0022"},{"time":false}] ] # );
dump $envres;
my ($min, $max) = minmax(map {$_->{time}} @{$envres->[2]});
dump $min, $max;
__END__
[
  [],
  [],
  [
    { time => 0.0022 },
    { time => bless(do{\(my $o = 0)}, "JSON::PP::Boolean") },
  ],
]
Segmentation fault (core dumped)
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