[commit: ghc] master: Extend Windows runtime loader libsearch (f56fc7f)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/f56fc7f7fe72f96348d663a83f736c4c8b12b08b/ghc

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

commit f56fc7f7fe72f96348d663a83f736c4c8b12b08b
Author: Tamar Christina <tamar at zhox.com>
Date:   Thu Mar 2 15:14:34 2017 -0500

    Extend Windows runtime loader libsearch
    
    This adds `.obj` extension to the list of valid
    object file (we really shouldn't be using extensions
    but instead trying to read the file and see if the header
    makes sense.). Microsoft compilers use .obj instead of .o
    for object files.
    
    This also adds support to finding static archives when the
    "lib" prefix is already in the filename. e.g. `-llibfoo` to
    find `libfoo.a`. This is inline with binutils.
    
    Test Plan: ./validate
    
    Reviewers: simonmar, erikd, bgamari, hvr, austin
    
    Reviewed By: bgamari
    
    Subscribers: RyanGlScott, thomie, #ghc_windows_task_force
    
    Differential Revision: https://phabricator.haskell.org/D3082


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

f56fc7f7fe72f96348d663a83f736c4c8b12b08b
 compiler/ghci/Linker.hs  | 11 +++++++----
 rts/linker/LoadArchive.c |  5 ++++-
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/compiler/ghci/Linker.hs b/compiler/ghci/Linker.hs
index ebd27b0..49f57e5 100644
--- a/compiler/ghci/Linker.hs
+++ b/compiler/ghci/Linker.hs
@@ -1364,7 +1364,9 @@ locateLib hsc_env is_hs dirs lib
 
      obj_file     = lib <.> "o"
      dyn_obj_file = lib <.> "dyn_o"
-     arch_file = "lib" ++ lib ++ lib_tag <.> "a"
+     arch_files = [ "lib" ++ lib ++ lib_tag <.> "a"
+                  , lib <.> "a" -- native code has no lib_tag
+                  ]
      lib_tag = if is_hs && loading_profiled_hs_libs then "_p" else ""
 
      loading_profiled_hs_libs = interpreterProfiled dflags
@@ -1385,9 +1387,10 @@ locateLib hsc_env is_hs dirs lib
 
      findObject    = liftM (fmap Object)  $ findFile dirs obj_file
      findDynObject = liftM (fmap Object)  $ findFile dirs dyn_obj_file
-     findArchive   = let local  = liftM (fmap Archive) $ findFile dirs arch_file
-                         linked = liftM (fmap Archive) $ searchForLibUsingGcc dflags arch_file dirs
-                     in liftM2 (<|>) local linked
+     findArchive   = let local  name = liftM (fmap Archive) $ findFile dirs name
+                         linked name = liftM (fmap Archive) $ searchForLibUsingGcc dflags name dirs
+                         check name = apply [local name, linked name]
+                     in  apply (map check arch_files)
      findHSDll     = liftM (fmap DLLPath) $ findFile dirs hs_dyn_lib_file
      findDll       = liftM (fmap DLLPath) $ findFile dirs dyn_lib_file
      findSysDll    = fmap (fmap $ DLL . dropExtension . takeFileName) $ findSystemLibrary hsc_env so_name
diff --git a/rts/linker/LoadArchive.c b/rts/linker/LoadArchive.c
index 7d9dc22..62922a7 100644
--- a/rts/linker/LoadArchive.c
+++ b/rts/linker/LoadArchive.c
@@ -457,8 +457,11 @@ static HsInt loadArchive_ (pathchar *path)
 
         DEBUG_LOG("Found member file `%s'\n", fileName);
 
+        /* TODO: Stop relying on file extensions to determine input formats.
+                 Instead try to match file headers. See Trac #13103.  */
         isObject = (thisFileNameSize >= 2 && strncmp(fileName + thisFileNameSize - 2, ".o"  , 2) == 0)
-                || (thisFileNameSize >= 4 && strncmp(fileName + thisFileNameSize - 4, ".p_o", 4) == 0);
+                || (thisFileNameSize >= 4 && strncmp(fileName + thisFileNameSize - 4, ".p_o", 4) == 0)
+                || (thisFileNameSize >= 4 && strncmp(fileName + thisFileNameSize - 4, ".obj", 4) == 0);
 
 #if defined(OBJFORMAT_PEi386)
         /*