skarnet.org packages: fix darwin build

The configure scripts have been changed so that `--build` is now the
way to specify (non-cross compiling) build target, which is necessary
on darwin for binary compatibility across darwin versions.

pkgs/development/libraries/skalibs/default.nix

@@ -30,7 +30,7 @@ in stdenv.mkDerivation rec {
   # Explicitly setting target ensures code can be compiled against a skalibs
   # binary built on a different version of darwin.
   # http://www.skarnet.org/cgi-bin/archive.cgi?1:mss:623:heiodchokfjdkonfhdph
-  ++ (stdenv.lib.optional stdenv.isDarwin "--target=${stdenv.system}");
+  ++ (stdenv.lib.optional stdenv.isDarwin "--build=${stdenv.system}");
 
   meta = {
     homepage = http://skarnet.org/software/skalibs/;

pkgs/tools/misc/execline/default.nix

@@ -28,7 +28,7 @@ in stdenv.mkDerivation rec {
     "--with-dynlib=${skalibs}/lib"
   ]
   ++ (if stdenv.isDarwin then [ "--disable-shared" ] else [ "--enable-shared" ])
-  ++ (stdenv.lib.optional stdenv.isDarwin "--target=${stdenv.system}");
+  ++ (stdenv.lib.optional stdenv.isDarwin "--build=${stdenv.system}");
 
   meta = {
     homepage = http://skarnet.org/software/execline/;

pkgs/tools/misc/s6-portable-utils/default.nix

@@ -13,17 +13,19 @@ stdenv.mkDerivation rec {
 
   dontDisableStatic = true;
 
-  nativeBuildInputs = []
-  ++ optional stdenv.isDarwin gcc;
-
   configureFlags = [
     "--enable-absolute-paths"
     "--with-sysdeps=${skalibs}/lib/skalibs/sysdeps"
     "--with-include=${skalibs}/include"
     "--with-lib=${skalibs}/lib"
     "--with-dynlib=${skalibs}/lib"
-  ];
-
+  ]
+  # On darwin, the target triplet from -dumpmachine includes version number, but
+  # skarnet.org software uses the triplet to test binary compatibility.
+  # Explicitly setting target ensures code can be compiled against a skalibs
+  # binary built on a different version of darwin.
+  # http://www.skarnet.org/cgi-bin/archive.cgi?1:mss:623:heiodchokfjdkonfhdph
+  ++ (stdenv.lib.optional stdenv.isDarwin "--build=${stdenv.system}");
 
   meta = {
     homepage = http://www.skarnet.org/software/s6-portable-utils/;

pkgs/tools/networking/s6-dns/default.nix

@@ -28,7 +28,7 @@ in stdenv.mkDerivation rec {
     "--with-dynlib=${skalibs}/lib"
   ]
   ++ (if stdenv.isDarwin then [ "--disable-shared" ] else [ "--enable-shared" ])
-  ++ (stdenv.lib.optional stdenv.isDarwin "--target=${stdenv.system}");
+  ++ (stdenv.lib.optional stdenv.isDarwin "--build=${stdenv.system}");
 
   meta = {
     homepage = http://www.skarnet.org/software/s6-dns/;

pkgs/tools/networking/s6-networking/default.nix

@@ -34,7 +34,7 @@ in stdenv.mkDerivation rec {
     "--with-dynlib=${s6}/lib"
     "--with-dynlib=${s6Dns}/lib"
   ]
-  ++ (stdenv.lib.optional stdenv.isDarwin "--target=${stdenv.system}");
+  ++ (stdenv.lib.optional stdenv.isDarwin "--build=${stdenv.system}");
 
   meta = {
     homepage = http://www.skarnet.org/software/s6-networking/;

pkgs/tools/system/s6-rc/default.nix

@@ -32,7 +32,7 @@ in stdenv.mkDerivation rec {
     "--with-dynlib=${s6}/lib"
   ]
   ++ (if stdenv.isDarwin then [ "--disable-shared" ] else [ "--enable-shared" ])
-  ++ (stdenv.lib.optional stdenv.isDarwin "--target=${stdenv.system}");
+  ++ (stdenv.lib.optional stdenv.isDarwin "--build=${stdenv.system}");
 
   meta = {
     homepage = http://skarnet.org/software/s6-rc/;

pkgs/tools/system/s6/default.nix

@@ -29,7 +29,7 @@ in stdenv.mkDerivation rec {
     "--with-dynlib=${execline}/lib"
   ]
   ++ (if stdenv.isDarwin then [ "--disable-shared" ] else [ "--enable-shared" ])
-  ++ (stdenv.lib.optional stdenv.isDarwin "--target=${stdenv.system}");
+  ++ (stdenv.lib.optional stdenv.isDarwin "--build=${stdenv.system}");
 
   meta = {
     homepage = http://www.skarnet.org/software/s6/;