Merge pull request #1386 from 23Skidoo/ghc-head-fixes

Fix building of executables that use TH with dyn-by-default GHC. 

Cabal/Cabal.cabal

@@ -91,6 +91,10 @@ extra-source-files:
   tests/PackageTests/PreProcess/Foo.hsc
   tests/PackageTests/PreProcess/Main.hs
   tests/PackageTests/PreProcess/my.cabal
+  tests/PackageTests/TemplateHaskell/vanilla/Exe.hs
+  tests/PackageTests/TemplateHaskell/vanilla/Lib.hs
+  tests/PackageTests/TemplateHaskell/vanilla/TH.hs
+  tests/PackageTests/TemplateHaskell/vanilla/my.cabal
   tests/PackageTests/TemplateHaskell/dynamic/Exe.hs
   tests/PackageTests/TemplateHaskell/dynamic/Lib.hs
   tests/PackageTests/TemplateHaskell/dynamic/TH.hs

Cabal/Distribution/Simple/GHC.hs

@@ -713,10 +713,11 @@ buildLib verbosity pkg_descr lbi lib clbi = do
   unless (null (libModules lib)) $
     do let vanilla = whenVanillaLib forceVanillaLib (runGhcProg vanillaOpts)
            shared  = whenSharedLib  forceSharedLib  (runGhcProg sharedOpts)
-       if dynamicTooSupported &&
-          (forceVanillaLib || withVanillaLib lbi) &&
-          (forceSharedLib  || withSharedLib  lbi)  &&
-          null (ghcSharedOptions libBi)
+           useDynToo = dynamicTooSupported &&
+                       (forceVanillaLib || withVanillaLib lbi) &&
+                       (forceSharedLib  || withSharedLib  lbi) &&
+                       null (ghcSharedOptions libBi)
+       if useDynToo
            then runGhcProg vanillaSharedOpts
            else if isGhcDynamic then do shared;  vanilla
                                 else do vanilla; shared
@@ -881,7 +882,9 @@ buildExe verbosity _pkg_descr lbi
 
   -- build executables
 
-  srcMainFile <- findFile (exeDir : hsSourceDirs exeBi) modPath
+  srcMainFile         <- findFile (exeDir : hsSourceDirs exeBi) modPath
+  isGhcDynamic        <- ghcDynamic verbosity ghcProg
+  dynamicTooSupported <- ghcSupportsDynamicToo verbosity ghcProg
 
   let isHaskellMain = elem (takeExtension srcMainFile) [".hs", ".lhs"]
       cSrcs         = cSources exeBi ++ [srcMainFile | not isHaskellMain]
@@ -909,12 +912,37 @@ buildExe verbosity _pkg_descr lbi
                       ghcOptObjSuffix      = toFlag "dyn_o",
                       ghcOptExtra          = ghcSharedOptions exeBi
                     }
-
-      compileOpts | withProfExe lbi = profOpts
+      dynTooOpts = staticOpts `mappend` mempty {
+                      ghcOptExtra = ["-dynamic-too",
+                                     "-dynhisuf", "dyn_hi",
+                                     "-dynosuf", "dyn_o"]
+                    }
+      commonOpts  | withProfExe lbi = profOpts
                   | withDynExe  lbi = dynOpts
                   | otherwise       = staticOpts
-
-      linkOpts = compileOpts `mappend` mempty {
+      compileOpts | useDynToo = dynTooOpts
+                  | otherwise = commonOpts
+      withStaticExe = (not $ withProfExe lbi) && (not $ withDynExe lbi)
+
+      -- For building exe's that use TH with -prof or -dynamic we actually have
+      -- to build twice, once without -prof/-dynamic and then again with
+      -- -prof/-dynamic. This is because the code that TH needs to run at
+      -- compile time needs to be the vanilla ABI so it can be loaded up and run
+      -- by the compiler.
+      -- With dynamic-by-default GHC the TH object files loaded at compile-time
+      -- need to be .dyn_o instead of .o.
+      doingTH = EnableExtension TemplateHaskell `elem` allExtensions exeBi
+      -- Should we use -dynamic-too instead of compilng twice?
+      useDynToo = dynamicTooSupported && isGhcDynamic
+                  && doingTH && withStaticExe && null (ghcSharedOptions exeBi)
+      compileTHOpts | isGhcDynamic = dynOpts
+                    | otherwise    = staticOpts
+      compileForTH
+        | useDynToo    = False
+        | isGhcDynamic = doingTH && (withProfExe lbi || withStaticExe)
+        | otherwise    = doingTH && (withProfExe lbi || withDynExe lbi)
+
+      linkOpts = commonOpts `mappend` mempty {
                       ghcOptLinkOptions    = PD.ldOptions exeBi,
                       ghcOptLinkLibs       = extraLibs exeBi,
                       ghcOptLinkLibPath    = extraLibDirs exeBi,
@@ -923,15 +951,9 @@ buildExe verbosity _pkg_descr lbi
                       ghcOptExtra          = ["-no-hs-main" | not isHaskellMain ]
                  }
 
-  -- For building exe's for profiling that use TH we actually
-  -- have to build twice, once without profiling and then again
-  -- with profiling. This is because the code that TH needs to
-  -- run at compile time needs to be the vanilla ABI so it can
-  -- be loaded up and run by the compiler.
-  when ((withProfExe lbi || withDynExe lbi) &&
-        EnableExtension TemplateHaskell `elem` allExtensions exeBi) $
-    runGhcProg staticOpts { ghcOptNoLink = toFlag True }
-    --TODO: do we also need to play the static vs dynamic games here?
+  -- Build static/dynamic object files for TH, if needed.
+  when compileForTH $
+    runGhcProg compileTHOpts { ghcOptNoLink = toFlag True }
 
   runGhcProg compileOpts { ghcOptNoLink = toFlag True }
 

Cabal/tests/PackageTests.hs

@@ -71,6 +71,8 @@ tests version inplaceSpec =
     , hunit "BenchmarkExeV10/Test"
       PackageTests.BenchmarkExeV10.Check.checkBenchmark
     , hunit "BenchmarkOptions" PackageTests.BenchmarkOptions.Check.suite
+    , hunit "TemplateHaskell/vanilla"
+      PackageTests.TemplateHaskell.Check.vanilla
     , hunit "TemplateHaskell/profiling"
       PackageTests.TemplateHaskell.Check.profiling
     , hunit "TemplateHaskell/dynamic"

Cabal/tests/PackageTests/TemplateHaskell/Check.hs

@@ -4,6 +4,13 @@ import PackageTests.PackageTester
 import System.FilePath
 import Test.HUnit
 
+vanilla :: Test
+vanilla = TestCase $ do
+  let spec = PackageSpec ("PackageTests" </>
+                          "TemplateHaskell" </> "vanilla") []
+  result <- cabal_build spec
+  assertBuildSucceeded result
+
 profiling :: Test
 profiling = TestCase $ do
    let flags = ["--enable-library-profiling"

Cabal/tests/PackageTests/TemplateHaskell/dynamic/Exe.hs

@@ -3,4 +3,4 @@ module Main where
 
 import TH
 
-main = print $(splice)
\ No newline at end of file
+main = print $(splice)

Cabal/tests/PackageTests/TemplateHaskell/profiling/Exe.hs

@@ -3,4 +3,4 @@ module Main where
 
 import TH
 
-main = print $(splice)
\ No newline at end of file
+main = print $(splice)

Cabal/tests/PackageTests/TemplateHaskell/vanilla/Exe.hs

+{-# LANGUAGE TemplateHaskell #-}
+module Main where
+
+import TH
+
+main = print $(splice)

Cabal/tests/PackageTests/TemplateHaskell/vanilla/Lib.hs

+{-# LANGUAGE TemplateHaskell #-}
+module Lib where
+
+import TH
+
+val = $(splice)

Cabal/tests/PackageTests/TemplateHaskell/vanilla/TH.hs

+{-# LANGUAGE TemplateHaskell #-}
+module TH where
+
+splice = [| () |]

Cabal/tests/PackageTests/TemplateHaskell/vanilla/my.cabal

+Name: templateHaskell
+Version: 0.1
+Build-Type: Simple
+Cabal-Version: >= 1.2
+
+Library
+    Exposed-Modules: Lib
+    Other-Modules: TH
+    Build-Depends: base, template-haskell
+    Extensions: TemplateHaskell
+
+Executable main
+    Main-is: Exe.hs
+    Build-Depends: base, template-haskell
+    Extensions: TemplateHaskell