pysetup.mk: Add an explicit `gen' target, and make `all' depend on it.

I plan to add support for multiple `python' versions building in
parallel in the same working tree.  But generated files are shared
between `python' versions, and there will be a mess if things happen in
the wrong order.

diff --git a/pysetup.mk b/pysetup.mk
index 0e7a218..09dd7b0 100644 (file)
--- a/pysetup.mk
+++ b/pysetup.mk
@@ -15,8 +15,12 @@ distdir                      := $(shell $(PYTHON) setup.py -q distdir)
 ###--------------------------------------------------------------------------
 ### Useful targets implemented by the `setup.py' program.
 
+PYTARGETS              += gen
+CMD-gen                        ?= build_gen
+
 PYTARGETS              += all
 CMD-all                        ?= build
+all:: gen
 
 PYTARGETS              += clean
 OPTS-clean             ?= --all