make sure libraries/dph/ghc.mk is included after the other DPH ghc.mk

files, so that it can refer to variables defined there.  (necessary,
but perhaps not sufficient, to fix the DPH build bugs)

ghc.mk

@@ -616,7 +616,10 @@ endif
 # ----------------------------------------------
 # Actually include all the sub-ghc.mk's
 
-include $(patsubst %, %/ghc.mk, $(BUILD_DIRS))
+# BUILD_DIRS_EXTRA needs to come after BUILD_DIRS, because stuff in
+# libraries/dph/ghc.mk refers to stuff defined earlier, in particular
+# things like $(libraries/dph/dph-base_dist-install_GHCI_LIB)
+include $(patsubst %, %/ghc.mk, $(BUILD_DIRS) $(BUILD_DIRS_EXTRA))
 
 # A useful pseudo-target (must be after the include above, because it needs
 # the value of things like $(libraries/base_dist-install_v_LIB).

rules/extra-packages.mk

@@ -27,9 +27,13 @@
 #	  add P to the list of packages
 
 define extra-packages
+
+# Collects some dirs containing ghc.mk files that we need to include:
+BUILD_DIRS_EXTRA=
+
 $$(foreach p,$$(patsubst libraries/%,%,$$(wildcard $$(shell grep '^[^ #][^ ]* \+\(dph\|extra\) \+[^ ]\+ \+[^ ]\+$$$$' packages | sed 's/ .*//'))),\
     $$(if $$(wildcard libraries/$$p/ghc-packages),\
-        $$(eval BUILD_DIRS += libraries/$$p) \
+        $$(eval BUILD_DIRS_EXTRA += libraries/$$p) \
         $$(foreach q,$$(shell cat libraries/$$p/ghc-packages2),$$(eval $$(call extra-package,$$p,$$p/$$q))),\
         $$(eval $$(call extra-package,$$p,$$p)))\
 )