Add missing files from #7702's test

tests/simplCore/should_compile/T7702.hs

@@ -0,0 +1,7 @@
+-- The contents of this file are irrelevant. It is merely
+-- the target for compilation by the T7702Plugin, which
+-- exhibits the space leak in Trac #7702
+module Main where
+
+main :: IO ()
+main = return ()

tests/simplCore/should_compile/T7702.stderr

@@ -0,0 +1 @@
+T7702Plugin

tests/simplCore/should_compile/T7702plugin/Makefile

@@ -0,0 +1,20 @@
+TOP=../../../..
+include $(TOP)/mk/boilerplate.mk
+include $(TOP)/mk/test.mk
+
+clean.%:
+	rm -rf pkg.$*
+
+HERE := $(abspath .)
+$(eval $(call canonicalise,HERE))
+
+package.%:
+	$(MAKE) clean.$*
+	mkdir pkg.$*
+	"$(TEST_HC)" -outputdir pkg.$* --make -v0 -o pkg.$*/setup Setup.hs
+
+	echo "[]" > pkg.$*/local.package.conf
+
+	pkg.$*/setup configure --distdir pkg.$*/dist -v0 $(CABAL_PLUGIN_BUILD) --prefix="$(HERE)/pkg.$*/install" --with-compiler="$(TEST_HC)" --with-hc-pkg="$(GHC_PKG)" --package-db=pkg.$*/local.package.conf
+	pkg.$*/setup build     --distdir pkg.$*/dist -v0
+	pkg.$*/setup install   --distdir pkg.$*/dist -v0

tests/simplCore/should_compile/T7702plugin/Setup.hs

@@ -0,0 +1,3 @@
+import Distribution.Simple
+
+main = defaultMain

tests/simplCore/should_compile/T7702plugin/T7702Plugin.hs

@@ -0,0 +1,51 @@
+module T7702Plugin ( plugin )  where
+
+import GhcPlugins
+
+-- A plugin that does nothing but tickle CoreM's writer.
+plugin :: Plugin
+plugin = defaultPlugin { installCoreToDos = install }
+    where
+        install :: [CommandLineOption] -> [CoreToDo] -> CoreM [CoreToDo]
+        install _ todos = do
+            reinitializeGlobals
+
+            putMsgS "T7702Plugin"
+
+            -- 1 million times, so the allocation in this plugin dominates allocation due
+            -- to other compiler flags and the test framework can easily catch the difference
+            -- can't use replicateM_ because it causes its own problems
+            nothingX100000 ; nothingX100000 ; nothingX100000 ; nothingX100000 ; nothingX100000
+            nothingX100000 ; nothingX100000 ; nothingX100000 ; nothingX100000 ; nothingX100000
+
+            return todos
+
+-- this will result in a call to plusWriter in CoreM's
+-- >>= implementation, which was causing the space leak
+nothing :: CoreM ()
+nothing = liftIO (return ())
+
+nothingX10 :: CoreM ()
+nothingX10 = do
+    nothing ; nothing ; nothing ; nothing ; nothing
+    nothing ; nothing ; nothing ; nothing ; nothing
+
+nothingX100 :: CoreM ()
+nothingX100 = do
+    nothingX10 ; nothingX10 ; nothingX10 ; nothingX10 ; nothingX10
+    nothingX10 ; nothingX10 ; nothingX10 ; nothingX10 ; nothingX10
+
+nothingX1000 :: CoreM ()
+nothingX1000 = do
+    nothingX100 ; nothingX100 ; nothingX100 ; nothingX100 ; nothingX100
+    nothingX100 ; nothingX100 ; nothingX100 ; nothingX100 ; nothingX100
+
+nothingX10000 :: CoreM ()
+nothingX10000 = do
+    nothingX1000 ; nothingX1000 ; nothingX1000 ; nothingX1000 ; nothingX1000
+    nothingX1000 ; nothingX1000 ; nothingX1000 ; nothingX1000 ; nothingX1000
+
+nothingX100000 :: CoreM ()
+nothingX100000 = do
+    nothingX10000 ; nothingX10000 ; nothingX10000 ; nothingX10000 ; nothingX10000
+    nothingX10000 ; nothingX10000 ; nothingX10000 ; nothingX10000 ; nothingX10000

tests/simplCore/should_compile/T7702plugin/T7702plugin.cabal

@@ -0,0 +1,13 @@
+Name:           T7702plugin
+Version:        0.1
+Synopsis:       Plugin which tests space leak fix in Trac #7702
+Cabal-Version:  >= 1.2
+Build-Type:     Simple
+Author:         Andrew Farmer
+
+Library
+    Build-Depends:
+        base,
+        ghc >= 7.2.1
+    Exposed-Modules:
+        T7702Plugin