dwarf_add_expr_gen(3) on FreeBSD
The text 118526b4595e, 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 an operator to a location expression descriptor