haskell: use stack to obtain suitable GHC and cabal

.licenseignore

@@ -51,6 +51,7 @@ internal/*
 
 spec/haskell/cabal.sandbox.config
 spec/haskell/.cabal-sandbox/*
+spec/haskell/.stack-work/*
 spec/haskell/Setup.hs
 spec/haskell/configure
 spec/haskell/dist/*

spec/haskell/.gitignore

@@ -16,5 +16,6 @@
 
 # cabal dependencies 
 
+/.stack-work/
 /.cabal-sandbox/
 /cabal.sandbox.config

spec/haskell/Makefile

@@ -10,28 +10,48 @@
 
 
 BOOT_MODULES = Kernel/CSpace Kernel/Thread Kernel/FaultHandler \
-    Kernel/VSpace Kernel/Init Model/PSpace Object/TCB Object/CNode  \
+    Kernel/VSpace Kernel/Init Model/PSpace Object/TCB Object/CNode \
     Object/ObjectType Object/Endpoint Object/Interrupt
 
 BOOT_FILES=$(BOOT_MODULES:%=src/SEL4/%.lhs-boot)
 
-GHC=ghc
+# We use the cabal executable that we installed via stack,
+# and use the PATH from `stack exec` to find it.
+# However, cabal refuses to run when the GHC_PACKAGE_PATH
+# variable is set, so we use `stack-path` to clear
+# GHC_PACKAGE_PATH first.
+CABAL=stack exec -- ./stack-path cabal
 
 all: build pdf
 
-build: $(BOOT_FILES)
-	cabal sandbox init
-	cabal install --dependencies-only -w "$(GHC)"
-	cabal configure --configure-option="arm-kzm" -w "$(GHC)"
-	cabal build
+build: .stack-work $(BOOT_FILES)
+	$(CABAL) sandbox init
+	$(CABAL) install --dependencies-only
+	$(CABAL) configure --configure-option="arm-kzm"
+	$(CABAL) build
+
 pdf:
 	cd doc && make
 
+# We assume that if the .stack-work directory exists,
+# we don't need to install ghc, cabal, nor fetch the cabal
+# package database.
+# We make this assumption to avoid hitting the network on
+# every build.
+# However, this means that if .stack-work exists, but the
+# cabal package database is missing, the build will fail.
+.stack-work:
+	stack --install-ghc build cabal-install
+	$(CABAL) update
+
 %.lhs-boot: %.lhs mkhsboot.pl
 	perl mkhsboot.pl -l < $< > $@
 
 clean:
 	rm -f $(BOOT_FILES)
-	cabal clean
+	$(CABAL) clean
 
-.PHONY: all build pdf clean
+realclean:
+	rm -rf $(BOOT_FILES) dist .stack-work .cabal-sandbox cabal.sandbox.config
+
+.PHONY: all build pdf clean realclean

spec/haskell/SEL4.cabal

@@ -8,7 +8,7 @@
 -- @TAG(GD_GPL)
 --
 
-name:                   SEL4-ARM
+name:                   SEL4
 version:                1.4-pre
 cabal-version:          >= 1.18
 build-type:             Custom

spec/haskell/stack-path

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+# Copyright 2017, Data61, CSIRO
+#
+# This software may be distributed and modified according to the terms of
+# the GNU General Public License version 2. Note that NO WARRANTY is provided.
+# See "LICENSE_GPLv2.txt" for details.
+#
+# @TAG(DATA61_GPL)
+
+# Running cabal inside `stack exec` fails, because older versions of cabal
+# refuse to run with GHC_PACKAGE_PATH set.
+
+unset GHC_PACKAGE_PATH
+exec "$@"

spec/haskell/stack.yaml

@@ -0,0 +1,15 @@
+# Copyright 2017, Data61, CSIRO
+#
+# This software may be distributed and modified according to the terms of
+# the GNU General Public License version 2. Note that NO WARRANTY is provided.
+# See "LICENSE_GPLv2.txt" for details.
+#
+# @TAG(DATA61_GPL)
+
+resolver: lts-2.22
+
+packages: []
+extra-deps: []
+
+flags: {}
+extra-package-dbs: []