Merge pull request #50212 from matthewbauer/host-emulator

Add "emulator" function to systems

pkgs/development/libraries/talloc/default.nix

@@ -1,5 +1,6 @@
 { stdenv, fetchurl, python, pkgconfig, readline, libxslt
 , docbook_xsl, docbook_xml_dtd_42, fixDarwinDylibNames
+, buildPackages
 }:
 
 stdenv.mkDerivation rec {
@@ -10,10 +11,9 @@ stdenv.mkDerivation rec {
     sha256 = "1kk76dyav41ip7ddbbf04yfydb4jvywzi2ps0z2vla56aqkn11di";
   };
 
-  nativeBuildInputs = [ pkgconfig fixDarwinDylibNames ];
-  buildInputs = [
-    python readline libxslt docbook_xsl docbook_xml_dtd_42
-  ];
+  nativeBuildInputs = [ pkgconfig fixDarwinDylibNames python
+                        docbook_xsl docbook_xml_dtd_42 ];
+  buildInputs = [ readline libxslt ];
 
   prePatch = ''
     patchShebangs buildtools/bin/waf
@@ -23,10 +23,14 @@ stdenv.mkDerivation rec {
     "--enable-talloc-compat1"
     "--bundled-libraries=NONE"
     "--builtin-libraries=replace"
+  ] ++ stdenv.lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
+    "--cross-compile"
+    "--cross-execute=${stdenv.hostPlatform.emulator buildPackages}"
   ];
+  configurePlatforms = [];
 
   postInstall = ''
-    ar q $out/lib/libtalloc.a bin/default/talloc_[0-9]*.o
+    ${stdenv.cc.targetPrefix}ar q $out/lib/libtalloc.a bin/default/talloc_[0-9]*.o
   '';
 
   meta = with stdenv.lib; {