Add support for 'make help' in subdirectories

[ghc-hetmet.git] / ghc / Makefile

diff --git a/ghc/Makefile b/ghc/Makefile
index 664df24..7e6b416 100644 (file)
--- a/ghc/Makefile
+++ b/ghc/Makefile
@@ -1,3 +1,15 @@
+# -----------------------------------------------------------------------------
+#
+# (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
+#
+# -----------------------------------------------------------------------------
+
 dir = ghc
 TOP = ..
 SPEC_TARGETS = 1 2 3
@@ -14,3 +26,12 @@ include $(TOP)/mk/sub-makefile.mk
 3:
        +$(TOPMAKE) stage=3 all_ghc_stage3 compiler_stage3_NO_BUILD_DEPS=YES
 
+.PHONY: extra-help
+help : extra-help
+extra-help :
+       @echo "  make 1"
+       @echo "  make 2"
+       @echo "  make 3"
+       @echo
+       @echo "     Build the stage 1, 2 or 3 GHC respectively, omitting dependencies"
+       @echo "     and initial phases for speed."