! mkdir -p temp
read_rtlil <<EOT
module \test
  attribute \bottom_bound 3's101
  wire width 3 output 1 \a
  connect \a 3'001
end
EOT
write_rtlil temp/rtlil_signed_attribute.il
! grep -F -q "attribute \bottom_bound 3's101" temp/rtlil_signed_attribute.il
