FIX #1559, #1560. Rearrange the way we do ifBuildable...

ifBuildable now returns an exit code, with 1 indicating an unbuildable
non-core package, and 0 otherwise.  Hence we can now invoke the
recursive make from the shell, sidestepping the problems in #1559 and
#1560.

2 files changed, 44 insertions, 32 deletions

diff --git a/libraries/Makefile b/libraries/Makefile
index b3f9808157..0c845c9cf4 100644
--- a/libraries/Makefile
+++ b/libraries/Makefile
@@ -235,22 +235,29 @@ $(foreach SUBDIR,$(SUBDIRS),make.library.$(SUBDIR)):\
 make.library.%: stamp/configure.library.build$(CONFIGURE_STAMP_EXTRAS).% \
 		%/GNUmakefile \
                 %/setup/Setup ifBuildable/ifBuildable
-	ifBuildable/ifBuildable $* $(MAKE)
-	ifBuildable/ifBuildable $* setup/Setup register --inplace
+	if ifBuildable/ifBuildable $*; then \
+	  cd $* && \
+	  $(MAKE) $(MFLAGS) && \
+	  setup/Setup register --inplace; \
+	fi
 
 # Build the library using 'setup build' (not the default)
 $(foreach SUBDIR,$(SUBDIRS),build.library.$(SUBDIR)):\
 build.library.%: stamp/configure.library.build$(CONFIGURE_STAMP_EXTRAS).% \
                  %/setup/Setup ifBuildable/ifBuildable
-	ifBuildable/ifBuildable $* setup/Setup build \
-	                                $(addprefix --ghc-option=,$(GhcLibHcOpts))
+	if ifBuildable/ifBuildable $*; then \
+	  cd $* && \
+	  setup/Setup build $(addprefix --ghc-option=,$(GhcLibHcOpts)); \
+	fi
 
 $(foreach SUBDIR,$(SUBDIRS),$(SUBDIR)/GNUmakefile):\
 %/GNUmakefile: stamp/configure.library.build$(CONFIGURE_STAMP_EXTRAS).% \
                  %/setup/Setup ifBuildable/ifBuildable
 	$(RM) $*/GNUmakefile
 	cp Makefile.local $*
-	ifBuildable/ifBuildable $* setup/Setup makefile -f GNUmakefile
+	if ifBuildable/ifBuildable $*; then \
+	   cd $* && setup/Setup makefile -f GNUmakefile; \
+	fi
 
 .PHONY: doc
 
@@ -262,7 +269,9 @@ doc: $(foreach SUBDIR,$(SUBDIRS),doc.library.$(SUBDIR))
 $(foreach SUBDIR,$(SUBDIRS),doc.library.$(SUBDIR)):\
 doc.library.%: stamp/configure.library.build$(CONFIGURE_STAMP_EXTRAS).% \
                %/setup/Setup ifBuildable/ifBuildable
-	ifBuildable/ifBuildable $* setup/Setup haddock
+	if ifBuildable/ifBuildable $*; then \
+	  cd $* && setup/Setup haddock; \
+	fi
 
 .PHONY: distclean clean clean.library.%
 
@@ -307,7 +316,10 @@ install-docs:
 # Thus if you install without building then it will just break.
 $(foreach SUBDIR,$(SUBDIRS),install.library.$(SUBDIR)): \
 install.library.%: installPackage/installPackage ifBuildable/ifBuildable
-	ifBuildable/ifBuildable $* ../installPackage/installPackage $(prefix) $(bindir)/ghc-pkg
+	if ifBuildable/ifBuildable $*; then \
+	  cd $* && \
+	  ../installPackage/installPackage $(prefix) $(bindir)/ghc-pkg; \
+	fi
 
 .PHONY: binary-dist binary-dist.library.%
 
@@ -327,13 +339,15 @@ binary-dist: $(foreach SUBDIR,$(SUBDIRS),binary-dist.library.$(SUBDIR))
 $(foreach SUBDIR,$(SUBDIRS),binary-dist.library.$(SUBDIR)): \
 binary-dist.library.%:
 	$(MKDIRHIER) $(BIN_DIST_LIBDIR)/$*
-	ifBuildable/ifBuildable $* cp    $*.cabal      $(BIN_DIST_LIBDIR)/$*
-	ifBuildable/ifBuildable $* cp -a dist          $(BIN_DIST_LIBDIR)/$*
-	# Euch
-	ifBuildable/ifBuildable $* cp -aL include      $(BIN_DIST_LIBDIR)/$* || :
-	ifBuildable/ifBuildable $* $(FIND) $(BIN_DIST_LIBDIR)/$*/dist \
-	     \( -name "*_split" -o -name "autogen" \) | xargs rm -rf
-	ifBuildable/ifBuildable $* $(FIND) $(BIN_DIST_LIBDIR)/$*/dist \
+	if ifBuildable/ifBuildable $*; then \
+	  cd $* && \
+	  cp    $*.cabal      $(BIN_DIST_LIBDIR)/$* && \
+	  cp -a dist          $(BIN_DIST_LIBDIR)/$* && \
+	# Euch \
+	  (cp -aL include      $(BIN_DIST_LIBDIR)/$* || :) && \
+	  $(FIND) $(BIN_DIST_LIBDIR)/$*/dist \
+	     \( -name "*_split" -o -name "autogen" \) | xargs rm -rf && \
+	  $(FIND) $(BIN_DIST_LIBDIR)/$*/dist \
 	     \( \( -name "*.o" -o -name "*.p_o" \) -a ! -name "HS*" \) \
-	     -exec rm {} \;
-
+	     -exec rm {} \; ; \
+	fi
diff --git a/libraries/ifBuildable.hs b/libraries/ifBuildable.hs
index 3119aeefb7..95bebaf8d3 100644
--- a/libraries/ifBuildable.hs
+++ b/libraries/ifBuildable.hs
@@ -1,8 +1,9 @@
+-- Returns exitcode 0 if the given package is buildable or is a core package,
+-- and 1 otherwise.
 
 module Main (main) where
 
 import Control.Monad
-import System.Cmd
 import System.Directory
 import System.Environment
 import System.Exit
@@ -11,27 +12,24 @@ import System.IO
 main :: IO ()
 main = do args <- getArgs
           case args of
-              [] ->
-                  error "No package or command given"
-              [_] ->
-                  error "No command given"
-              package : prog : progArgs ->
-                  doit package prog progArgs
+              [package] ->
+                  doit package
+              _ ->
+                  error "Syntax: ifBuildable <package>"
 
-doit :: String -> String -> [String] -> IO ()
-doit package prog progArgs
+doit :: String -> IO ()
+doit package
  = do setCurrentDirectory package
       unbuildable <- doesFileExist "unbuildable"
-      if unbuildable
-         then do mustBeBuildables <- getMustBeBuildablePackages
+      if not unbuildable
+         then exitWith ExitSuccess
+         else do mustBeBuildables <- getMustBeBuildablePackages
                  if package `elem` mustBeBuildables
-                     then error (package ++ " is unbuildable")
-                     else hPutStrLn stderr "Warning: Package is unbuildable"
-         else do ec <- rawSystem prog progArgs
-                 exitWith ec
+                     then exitWith ExitSuccess
+                     else do hPutStrLn stderr "Warning: Package is unbuildable"
+                             exitWith (ExitFailure 1)
 
 getMustBeBuildablePackages :: IO [String]
 getMustBeBuildablePackages
  = do xs <- readFile "../core-packages"
       return $ filter ("readline" /=) $ lines xs
-