Fixes for LLVM 7

LLVM version numberinf changed recently. Previously, releases were numbered
4.0, 5.0 and 6.0 but with version 7, they dropped the redundant ".0".

Fix requires for Llvm detection and some code.

compiler/llvmGen/LlvmCodeGen.hs

@@ -3,7 +3,7 @@
 -- -----------------------------------------------------------------------------
 -- | This is the top-level module in the LLVM code generator.
 --
-module LlvmCodeGen ( llvmCodeGen, llvmFixupAsm ) where
+module LlvmCodeGen ( LlvmVersion (..), llvmCodeGen, llvmFixupAsm ) where
 
 #include "HsVersions.h"
 

compiler/llvmGen/LlvmCodeGen/Base.hs

@@ -13,7 +13,7 @@ module LlvmCodeGen.Base (
         LiveGlobalRegs,
         LlvmUnresData, LlvmData, UnresLabel, UnresStatic,
 
-        LlvmVersion, supportedLlvmVersion, llvmVersionStr,
+        LlvmVersion (..), supportedLlvmVersion, llvmVersionStr,
 
         LlvmM,
         runLlvm, liftStream, withClearVars, varLookup, varInsert,
@@ -177,14 +177,25 @@ llvmPtrBits dflags = widthInBits $ typeWidth $ gcWord dflags
 --
 
 -- | LLVM Version Number
-type LlvmVersion = (Int, Int)
+data LlvmVersion
+    = LlvmVersion Int
+    | LlvmVersionOld Int Int
+    deriving Eq
+
+-- Custom show instance for backwards compatibility.
+instance Show LlvmVersion where
+  show (LlvmVersion maj) = show maj
+  show (LlvmVersionOld maj min) = show maj ++ "." ++ show min
 
 -- | The LLVM Version that is currently supported.
 supportedLlvmVersion :: LlvmVersion
-supportedLlvmVersion = sUPPORTED_LLVM_VERSION
+supportedLlvmVersion = LlvmVersion sUPPORTED_LLVM_VERSION
 
 llvmVersionStr :: LlvmVersion -> String
-llvmVersionStr (major, minor) = show major ++ "." ++ show minor
+llvmVersionStr v =
+  case v of
+    LlvmVersion maj -> show maj
+    LlvmVersionOld maj min -> show maj ++ "." ++ show min
 
 -- ----------------------------------------------------------------------------
 -- * Environment Handling

compiler/main/DriverPipeline.hs

@@ -56,7 +56,7 @@ import StringBuffer     ( hGetStringBuffer, hPutStringBuffer )
 import BasicTypes       ( SuccessFlag(..) )
 import Maybes           ( expectJust )
 import SrcLoc
-import LlvmCodeGen      ( llvmFixupAsm )
+import LlvmCodeGen      ( LlvmVersion (..), llvmFixupAsm )
 import MonadUtils
 import GHC.Platform
 import TcRnTypes
@@ -2038,7 +2038,8 @@ getBackendDefs :: DynFlags -> IO [String]
 getBackendDefs dflags | hscTarget dflags == HscLlvm = do
     llvmVer <- figureLlvmVersion dflags
     return $ case llvmVer of
-               Just n -> [ "-D__GLASGOW_HASKELL_LLVM__=" ++ format n ]
+               Just (LlvmVersion n) -> [ "-D__GLASGOW_HASKELL_LLVM__=" ++ format (n,0) ]
+               Just (LlvmVersionOld m n) -> [ "-D__GLASGOW_HASKELL_LLVM__=" ++ format (m,n) ]
                _      -> []
   where
     format (major, minor)

compiler/main/SysTools/Tasks.hs

@@ -23,7 +23,7 @@ import System.IO
 import System.Process
 import GhcPrelude
 
-import LlvmCodeGen.Base (llvmVersionStr, supportedLlvmVersion)
+import LlvmCodeGen.Base (LlvmVersion (..), llvmVersionStr, supportedLlvmVersion)
 
 import SysTools.Process
 import SysTools.Info
@@ -200,7 +200,7 @@ runClang dflags args = do
     )
 
 -- | Figure out which version of LLVM we are running this session
-figureLlvmVersion :: DynFlags -> IO (Maybe (Int, Int))
+figureLlvmVersion :: DynFlags -> IO (Maybe LlvmVersion)
 figureLlvmVersion dflags = do
   let (pgm,opts) = pgm_lc dflags
       args = filter notNull (map showOpt opts)
@@ -222,8 +222,10 @@ figureLlvmVersion dflags = do
               vline <- dropWhile (not . isDigit) `fmap` hGetLine pout
               v     <- case span (/= '.') vline of
                         ("",_)  -> fail "no digits!"
-                        (x,y) -> return (read x
-                                        , read $ takeWhile isDigit $ drop 1 y)
+                        (x,"") -> return $ LlvmVersion (read x)
+                        (x,y) -> return $ LlvmVersionOld
+                                            (read x)
+                                            (read $ takeWhile isDigit $ drop 1 y)
 
               hClose pin
               hClose pout

configure.ac

@@ -628,7 +628,7 @@ AC_SUBST([LibtoolCmd])
 # tools we are looking for. In the past, GHC supported a number of
 # versions of LLVM simultaneously, but that stopped working around
 # 3.5/3.6 release of LLVM.
-LlvmVersion=7.0
+LlvmVersion=7
 AC_SUBST([LlvmVersion])
 sUPPORTED_LLVM_VERSION=$(echo \($LlvmVersion\) | sed 's/\./,/')
 AC_DEFINE_UNQUOTED([sUPPORTED_LLVM_VERSION], ${sUPPORTED_LLVM_VERSION}, [The supported LLVM version number])