+# -----------------------------------------------------------------------------
+#
+# (c) 2009 The University of Glasgow
+#
+# This file is part of the GHC build system.
+#
+# To understand how the build system works and how to modify it, see
+# http://hackage.haskell.org/trac/ghc/wiki/Building/Architecture
+# http://hackage.haskell.org/trac/ghc/wiki/Building/Modifying
+#
+# -----------------------------------------------------------------------------
+
+# dummy-ghc
+
+# This is a tiny program to fool Cabal's configure that we have a
+# stage1 GHC, which lets us configure all the packages before we've
+# build stage1.
+
+utils/dummy-ghc_dist-dummy-ghc_MODULES = dummy-ghc
+utils/dummy-ghc_dist-dummy-ghc_PROG = dummy-ghc$(exeext)
+
+# depend on project.mk, so we pick up the new version number if it changes.
+utils/dummy-ghc/dist-dummy-ghc/build/dummy-ghc.hs : utils/dummy-ghc/ghc.mk $(MKDIRHIER) mk/project.mk compiler/main/DynFlags.hs
+ "$(MKDIRHIER)" $(dir $@)
+ "$(RM)" $(RM_OPTS) $@
+ echo 'import System.Environment' >> $@
+ echo 'import System.Cmd' >> $@
+ echo 'import System.Exit' >> $@
+ echo 'main :: IO ()' >> $@
+ echo 'main = do args <- getArgs' >> $@
+ echo ' case args of' >> $@
+ echo ' ["--numeric-version"] ->' >> $@
+ echo ' putStrLn "$(ProjectVersion)"' >> $@
+ echo ' ["--supported-languages"] ->' >> $@
+ echo ' mapM_ putStrLn extensions' >> $@
+ echo ' _ ->' >> $@
+ echo ' do e <- rawSystem "$(GHC_STAGE0)" args' >> $@
+ echo ' exitWith e' >> $@
+# This unpleasant sed script grabs the lines between the
+# xFlags ::
+# line and the
+# ]
+# line of compiler/main/DynFlags.hs, and if they look like
+# ( "PostfixOperators", ...
+# then it translates them into
+# ["PostfixOperators", "NoPostfixOperators"] ++
+# Tabs are a pain to handle portably with sed, so rather than worrying
+# about them we just use tr to remove them all before we start.
+ echo 'extensions :: [String]' >> $@
+ echo 'extensions =' >> $@
+ '$(TR)' -d '\t' < compiler/main/DynFlags.hs | '$(SED)' '/^xFlags/,/]/s/^ *( *"\([^"]*\)"[^"]*/ ["\1", "No\1"] ++/p;d' >> $@
+ echo ' []' >> $@
+
+# We don't build dummy-ghc with Cabal, so we need to pass -package
+# flags manually
+utils/dummy-ghc_dist-dummy-ghc_HC_OPTS = -package process
+$(eval $(call build-prog,utils/dummy-ghc,dist-dummy-ghc,0))
+