[commit: ghc] ghc-7.8: change deriveConstants to use nm in a POSIX way (fixes #8781) (e7563ec)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : ghc-7.8
Link       : http://ghc.haskell.org/trac/ghc/changeset/e7563ec2e03740074903036bf129fc972b623c23/ghc

>---------------------------------------------------------------

commit e7563ec2e03740074903036bf129fc972b623c23
Author: Karel Gardas <karel.gardas at centrum.cz>
Date:   Sat Mar 22 22:33:05 2014 +0100

    change deriveConstants to use nm in a POSIX way (fixes #8781)
    
    The patch provided by Christian Maeder <Christian.Maeder at dfki.de>
    
    Signed-off-by: Karel Gardas <karel.gardas at centrum.cz>
    Signed-off-by: Austin Seipp <austin at well-typed.com>
    (cherry picked from commit 045b28033a33a48d31951240a8cb35f2b78345dc)


>---------------------------------------------------------------

e7563ec2e03740074903036bf129fc972b623c23
 utils/deriveConstants/DeriveConstants.hs |   30 ++++++++++--------------------
 1 file changed, 10 insertions(+), 20 deletions(-)

diff --git a/utils/deriveConstants/DeriveConstants.hs b/utils/deriveConstants/DeriveConstants.hs
index 10df61c..54ee6a1 100644
--- a/utils/deriveConstants/DeriveConstants.hs
+++ b/utils/deriveConstants/DeriveConstants.hs
@@ -638,7 +638,7 @@ getWanted verbose tmpdir gccProgram gccFlags nmProgram
              oFile = tmpdir </> "tmp.o"
          writeFile cFile cStuff
          execute verbose gccProgram (gccFlags ++ ["-c", cFile, "-o", oFile])
-         xs <- readProcess nmProgram [oFile] ""
+         xs <- readProcess nmProgram ["-P", oFile] ""
          let ls = lines xs
              ms = map parseNmLine ls
              m = Map.fromList $ catMaybes ms
@@ -707,27 +707,17 @@ getWanted verbose tmpdir gccProgram gccFlags nmProgram
           doWanted (ClosurePayloadMacro {}) = []
           doWanted (FieldTypeGcptrMacro {}) = []
 
-          -- parseNmLine parses nm output that looks like
-          -- "0000000b C derivedConstantMAX_Vanilla_REG"
+          -- parseNmLine parses "nm -P" output that looks like
+          -- "_derivedConstantMAX_Vanilla_REG C b 0" Mac OS X
+          -- "derivedConstantMAX_Vanilla_REG C 0000000b 0000000b" GNU
+          -- "derivedConstantMAX_Vanilla_REG D        1        b" Solaris
           -- and returns ("MAX_Vanilla_REG", 11)
-          parseNmLine xs0 = case break (' ' ==) xs0 of
-                            (x1, ' ' : xs1) ->
-                                case break (' ' ==) xs1 of
-                                (x2, ' ' : x3) ->
-                                    case readHex x1 of
-                                    [(size, "")] ->
-                                        case x2 of
-                                        "C" ->
-                                            let x3' = case x3 of
-                                                      '_' : rest -> rest
-                                                      _          -> x3
-                                            in case stripPrefix prefix x3' of
-                                               Just name ->
-                                                   Just (name, size)
-                                               _ -> Nothing
-                                        _ -> Nothing
-                                    _ -> Nothing
+          parseNmLine xs0 = case words xs0 of
+                            [x0, x1, x2, x3] -> case stripPrefix prefix $ dropWhile (== '_') x0 of
+                              Just name -> case readHex $ if x1 == "C" then x2 else x3 of
+                                [(size, "")] -> Just (name, size)
                                 _ -> Nothing
+                              _ -> Nothing
                             _ -> Nothing
 
           -- If an Int value is larger than 2^28 or smaller