Debugging pkgsrc on DragonFly

[walt]

I've been using pkgsrc on DF for several months, but this is
the first time I've seen this kind of error, and I'm baffled.

The package is archivers/zip, which builds okay on NetBSD:

===> Overriding tools for zip-2.31
===> Creating toolchain wrappers for zip-2.31
===> Configuring for zip-2.31
===> Building for zip-2.31
/usr/bin/make -f unix/Makefile generic CC=gcc CPP="gcc -E"
sh unix/configure "gcc" "-O2 -I. -DUNIX -O2"
<snip>

But an attempted build on DF looks like this:

===> Overriding tools for zip-2.31
===> Creating toolchain wrappers for zip-2.31
===> Configuring for zip-2.31
===> Building for zip-2.31
`unix/Makefile' is up to date.
bmake: don't know how to make generic_gcc. Stop

It appears that bmake is treating Makefile as a target
to be built rather than as a Makefile.  A ktrace shows
attempts to find Makefile.c, Makefile.cc, Makefile.cpp,
and so on.

Then bmake looks for a file named generic_gcc, which
is actually the name of the target, not a filename.

Any pkgsrc fans out there who can give me a clue to
this puzzle?

Thanks!