x86_64: support PIC and therefore, Mac OS X in the NCG

[ghc-hetmet.git] / compiler / main / StaticFlags.hs

diff --git a/compiler/main/StaticFlags.hs b/compiler/main/StaticFlags.hs
index 9934e3e..1a026bd 100644 (file)
--- a/compiler/main/StaticFlags.hs
+++ b/compiler/main/StaticFlags.hs
@@ -52,6 +52,10 @@ module StaticFlags (
        opt_UF_UpdateInPlace,
        opt_UF_DearOp,
 
+       -- Related to linking
+       opt_PIC,
+       opt_Static,
+
        -- misc opts
        opt_IgnoreDotGhci,
        opt_ErrorSpans,
@@ -59,28 +63,26 @@ module StaticFlags (
        opt_HiVersion,
        opt_HistorySize,
        opt_OmitBlackHoling,
-       opt_Static,
        opt_Unregisterised,
        opt_EmitExternalCore,
-       opt_PIC,
        v_Ld_inputs,
+       tablesNextToCode
   ) where
 
 #include "HsVersions.h"
 
 import CmdLineParser
-import Config          ( cProjectVersionInt, cProjectPatchLevel,
-                         cGhcUnregisterised )
+import Config
 import FastString      ( FastString, mkFastString )
 import Util
 import Maybes          ( firstJust )
 import Panic           ( GhcException(..), ghcError )
 
-import EXCEPTION       ( throwDyn )
-import DATA_IOREF
-import UNSAFE_IO       ( unsafePerformIO )
-import Monad           ( when )
-import Char            ( isDigit )
+import Control.Exception ( throwDyn )
+import Data.IORef
+import System.IO.Unsafe        ( unsafePerformIO )
+import Control.Monad   ( when )
+import Data.Char       ( isDigit )
 import Data.List       ( sort, intersperse, nub )
 
 -----------------------------------------------------------------------------
@@ -100,15 +102,32 @@ parseStaticFlags args = do
                  | otherwise = []
 
   (more_leftover, errs) <- processArgs static_flags (unreg_flags ++ way_flags)
+
+    -- TABLES_NEXT_TO_CODE affects the info table layout.
+    -- Be careful to do this *after* all processArgs,
+    -- because evaluating tablesNextToCode involves looking at the global
+    -- static flags.  Those pesky global variables...
+  let cg_flags | tablesNextToCode = ["-optc-DTABLES_NEXT_TO_CODE"]
+              | otherwise        = []
+
   when (not (null errs)) $ ghcError (UsageError (unlines errs))
-  return (more_leftover++leftover)
+  return (cg_flags++more_leftover++leftover)
 
 
--- note that ordering is important in the following list: any flag which
+static_flags :: [(String, OptKind IO)]
+-- All the static flags should appear in this list.  It describes how each
+-- static flag should be processed.  Two main purposes:
+-- (a) if a command-line flag doesn't appear in the list, GHC can complain
+-- (b) a command-line flag may remove, or add, other flags; e.g. the "-fno-X" things
+--
+-- The common (PassFlag addOpt) action puts the static flag into the bunch of
+-- things that are searched up by the top-level definitions like
+--     opt_foo = lookUp FSLIT("-dfoo")
+
+-- Note that ordering is important in the following list: any flag which
 -- is a prefix flag (i.e. HasArg, Prefix, OptPrefix, AnySuffix) will override
 -- flags further down the list with the same prefix.
 
-static_flags :: [(String, OptKind IO)]
 static_flags = [
        ------- GHCi -------------------------------------------------------
      ( "ignore-dot-ghci", PassFlag addOpt )
@@ -127,7 +146,6 @@ static_flags = [
        -- ToDo: user ways
 
        ------ Debugging ----------------------------------------------------
-  ,  ( "dppr-noprags",     PassFlag addOpt )
   ,  ( "dppr-debug",       PassFlag addOpt )
   ,  ( "dppr-user-length", AnySuffix addOpt )
       -- rest of the debugging flags are dynamic
@@ -282,14 +300,26 @@ opt_UF_UpdateInPlace              = lookUp  FSLIT("-funfolding-update-in-place")
 
 opt_UF_DearOp   = ( 4 :: Int)
                        
+#if darwin_TARGET_OS && x86_64_TARGET_ARCH
+opt_PIC                         = True
+#else
+opt_PIC                         = lookUp FSLIT("-fPIC")
+#endif
 opt_Static                     = lookUp  FSLIT("-static")
 opt_Unregisterised             = lookUp  FSLIT("-funregisterised")
+
+-- Derived, not a real option.  Determines whether we will be compiling
+-- info tables that reside just before the entry code, or with an
+-- indirection to the entry code.  See TABLES_NEXT_TO_CODE in 
+-- includes/InfoTables.h.
+tablesNextToCode               = not opt_Unregisterised
+                                 && cGhcEnableTablesNextToCode == "YES"
+
 opt_EmitExternalCore           = lookUp  FSLIT("-fext-core")
 
 -- Include full span info in error messages, instead of just the start position.
 opt_ErrorSpans                 = lookUp FSLIT("-ferror-spans")
 
-opt_PIC                         = lookUp FSLIT("-fPIC")
 
 -- object files and libraries to be linked in are collected here.
 -- ToDo: perhaps this could be done without a global, it wasn't obvious
@@ -307,9 +337,6 @@ isStaticFlag f =
        "firrefutable-tuples",
        "fparallel",
        "fflatten",
-       "fsemi-tagging",
-       "flet-no-escape",
-       "femit-extern-decls",
        "fgransim",
        "fno-hi-version-check",
        "dno-black-holing",