dwarf_vendor_ext(3) on FreeBSD
The text 4293df27477f, as FreeBSD 12.0-RELEASE, FreeBSD 11.4-RELEASE, FreeBSD 11.3-RELEASE, FreeBSD 11.2-RELEASE, FreeBSD 11.1-RELEASE, FreeBSD 11.0-RELEASE shipped it.
add vendor-specific macro information to a DWARF producer instance