[commit: ghc] master: Fix annoying iOS linker warnings (#8208) (0451d85)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/0451d85d58363f8ce7ce552c19a00f9d535e6fed/ghc

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

commit 0451d85d58363f8ce7ce552c19a00f9d535e6fed
Author: Austin Seipp <aseipp at pobox.com>
Date:   Wed Sep 4 17:35:53 2013 -0500

    Fix annoying iOS linker warnings (#8208)
    
    Authored-by: Luke Iannini <lukexi at me.com>
    Signed-off-by: Austin Seipp <aseipp at pobox.com>


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

0451d85d58363f8ce7ce552c19a00f9d535e6fed
 compiler/main/DriverPipeline.hs |   15 +++++++++++++--
 compiler/main/SysTools.lhs      |    3 +++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/compiler/main/DriverPipeline.hs b/compiler/main/DriverPipeline.hs
index 8fc44ed..7c5bc90 100644
--- a/compiler/main/DriverPipeline.hs
+++ b/compiler/main/DriverPipeline.hs
@@ -1917,11 +1917,22 @@ linkBinary' staticLink dflags o_files dep_packages = do
                       -- on x86.
                       ++ (if sLdSupportsCompactUnwind mySettings &&
                              not staticLink &&
-                             platformOS   platform == OSDarwin &&
-                             platformArch platform `elem` [ArchX86, ArchX86_64]
+                             (platformOS platform == OSDarwin || platformOS platform == OSiOS) &&
+                             case platformArch platform of
+                               ArchX86 -> True
+                               ArchX86_64 -> True
+                               ArchARM {} -> True
+                               _ -> False
                           then ["-Wl,-no_compact_unwind"]
                           else [])
 
+                      -- '-no_pie'
+                      -- iOS uses 'dynamic-no-pic', so we must pass this to ld to suppress a warning; see #7722
+                      ++ (if platformOS platform == OSiOS &&
+                             not staticLink
+                          then ["-Wl,-no_pie"]
+                          else [])
+
                       -- '-Wl,-read_only_relocs,suppress'
                       -- ld gives loads of warnings like:
                       --     ld: warning: text reloc in _base_GHCziArr_unsafeArray_info to _base_GHCziArr_unsafeArray_closure
diff --git a/compiler/main/SysTools.lhs b/compiler/main/SysTools.lhs
index 6fe29a9..78255b7 100644
--- a/compiler/main/SysTools.lhs
+++ b/compiler/main/SysTools.lhs
@@ -681,6 +681,9 @@ getLinkerInfo' dflags = do
                  -- that doesn't support --version. We can just assume that's
                  -- what we're using.
                  return $ DarwinLD []
+               OSiOS -> 
+                 -- Ditto for iOS
+                 return $ DarwinLD []
                OSMinGW32 ->
                  -- GHC doesn't support anything but GNU ld on Windows anyway.
                  -- Process creation is also fairly expensive on win32, so