+# we could be more accurate here and add a dependency on
+# ghc/driver/package.conf, but that doesn't work too well because of
+# make's limited accuracy with modification times: when doing 'make
+# boot' in multiple packages, make won't detect that the package
+# configuration needs updating if it was updated already in the last
+# second.
+#
+# The stamp file goes in $(GHC_DRIVER_DIR), so that if someone happens
+# to 'make clean' in ghc without cleaning in libraries too, the packages
+# will be correctly re-installed.
+#
+STAMP_PKG_CONF = $(GHC_DRIVER_DIR)/stamp-pkg-conf-$(PACKAGE)
+CLEAN_FILES += $(STAMP_PKG_CONF)
+
+boot all :: $(STAMP_PKG_CONF)
+
+$(STAMP_PKG_CONF) : $(PACKAGE).conf.inplace $(PACKAGE).conf.installed