gnulib-tool: "refusing to do nothing"

[Ben Pfaff]

Until I update gnulib from CVS, "gnulib-tool --import" (without
any extra arguments) obtained the list of modules from gl_MODULES
in configure.ac and imported them into the source tree.

Now, it seems to no longer read gl_MODULES and this invocation
fails with "refusing to do nothing".  This is not the behavior I
expect or the documented behavior.

What is the new expected usage model?  (Or am I missing something
else?)

-- 
Ben Pfaff 
email: address@hidden
web: http://benpfaff.org