use warnings;
use strict;

use Inline C => Config =>
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

SV * foo(SV * nv) {
   double x = (double)SvNV(nv);
   return newSVnv(x);
}

EOC

print perl_foo(2.5), "\n";
print perl_foo(1.1), "\n"; # LINE 17

sub perl_foo {
    my $ret = foo($_[0]);
    if($_[0] - $ret) {warn "Loss of precision"} # LINE 21
    return $ret;
}

##</code><code>##

2.5
1.1

##</code><code>##

2.5
Loss of precision at double.pl line 21
1.10000000000000009