Want -zassert-deflib for ld
-zassert-deflib adds a way for ld to assert that there are no libraries that are being passed in with a -l option are found in the default search path. This is something that we generally want for building distributions to ensure that we're not linking against anything found in the platform itself. You can allow exceptions by passing -zassert-deflib=libfred.so.
This is most useful when trying to build ON and related pieces as it allows for us to go through and assert that we aren't using copies of libraries from the build machine as opposed to those from the proto area.
The astute observer may notice that the name here and interface here is not ideal, in this case it is easier to keep compatibility with Solaris rather than break it when most potential consumers (which are admittedly limited) would not have a good way to differentiate between which syntax should be used.