False positive for var in code removed by inlining

[dolmen]

Here is foo.pm:

package foo;
use strict;
use warnings;

use constant DEAD_CODE => 0;

sub test
{
    my $var;
    if (DEAD_CODE) {
        my $false_positive = 'xxx';    # <----- false positive
        bar($false_positive);
        $var = 'abc';
    } else {
        $var = 'def';
    }
}

1;

The $false_positive variable is in dead code that is removed by inlining as can be seen with B::Deparse:

$ perl -MO=Deparse foo.pm
package foo;
sub BEGIN {
    require strict;
    do {
        'strict'->import
    };
}
use constant ('DEAD_CODE', 0);
sub test {
    use warnings;
    use strict;
    my $var;
    do {
        $var = 'def'
    };
}
use warnings;
use strict;
'???';
foo.pm syntax OK

But Test::Vars reports $false_positive as an unused variable:

$ TEST_VERBOSE=1 perl -Ilib -MTest::Vars -E 'vars_ok(shift)' foo.pm
# checking foo in foo.pm ...
# $false_positive is used once in &foo::test 
not ok 1 - foo.pm
#   Failed test 'foo.pm'
#   at -e line 1.
# Tests were run but no plan was declared and done_testing() was not seen.