* remove a special case in sigmatch; distinct pointer types no longer match `nil` type
* add tests
* fixes tests
* Update changelog.md
Co-authored-by: konsumlamm <44230978+konsumlamm@users.noreply.github.com>
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
Co-authored-by: konsumlamm <44230978+konsumlamm@users.noreply.github.com>