binutils: minimize rebuilds after parent revert

Only revert the addition of the output and only on Darwin.

pkgs/development/tools/misc/binutils/default.nix

@@ -32,9 +32,18 @@ stdenv.mkDerivation rec {
     # This is needed, for instance, so that running "ldd" on a binary that is
     # PaX-marked to disable mprotect doesn't fail with permission denied.
     ./pt-pax-flags.patch
+
+    # Bfd looks in BINDIR/../lib for some plugins that don't
+    # exist. This is pointless (since users can't install plugins
+    # there) and causes a cycle between the lib and bin outputs, so
+    # get rid of it.
+    ./no-plugins.patch
   ];
 
-  outputs = [ "out" "info" ] ++ (optional (cross == null) "dev");
+  outputs = [ "out" ]
+    ++ optional (!stdenv.isDarwin) "lib" # problems in Darwin stdenv
+    ++ [ "info" ]
+    ++ optional (cross == null) "dev";
 
   nativeBuildInputs = [ bison ];
   buildInputs = [ zlib ];

pkgs/development/tools/misc/binutils/no-plugins.patch

@@ -0,0 +1,19 @@
+diff -ru binutils-2.27-orig/bfd/plugin.c binutils-2.27/bfd/plugin.c
+--- binutils-2.27-orig/bfd/plugin.c	2016-10-14 17:46:30.791315555 +0200
++++ binutils-2.27/bfd/plugin.c	2016-10-14 17:46:38.583298765 +0200
+@@ -333,6 +333,7 @@
+   if (plugin_program_name == NULL)
+     return found;
+ 
++#if 0
+   plugin_dir = concat (BINDIR, "/../lib/bfd-plugins", NULL);
+   p = make_relative_prefix (plugin_program_name,
+ 			    BINDIR,
+@@ -364,6 +365,7 @@
+   free (p);
+   if (d)
+     closedir (d);
++#endif
+ 
+   return found;
+ }