Looks like a bug in the XS version of reduce. The perl version doesn't seem to leak

#! perl -slw

sub reduce (&@) {
  my $code = shift;

  return shift unless @_ > 1;

  my $caller = caller;
  local(*{$caller."::a"}) = \my $a;
  local(*{$caller."::b"}) = \my $b;

  $a = shift;
  foreach (@_) {
    $b = $_;
    $a = &{$code}();
  }

  $a;
}


use strict;
#use List::Util qw[ reduce ];

sub s1 {
    my $r = shift;
    reduce{ $r->[0] } 1 .. 10;
}

while( 1 ) {
    my $t = map s1( $_ ), [1], [2], [3];
}
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