C:\>perl -MMath::MPFR -MTest::More -e "$got=Math::MPFR->new(2); $exp= Math::MPFR->new(2); ok($got != $exp) or  diag explain [$exp, $got]; done_testing();"
not ok 1
#   Failed test at -e line 1.
# [
#   bless( do{\(my $o = 46472664)}, 'Math::MPFR' ),
#   bless( do{\(my $o = 46474008)}, 'Math::MPFR' )
# ]
1..1
# Looks like you failed 1 test of 1.