From 47f2bf34f73eb29792eb307a67d6c529c6450b70 Mon Sep 17 00:00:00 2001
From: Sheena Artrip <sheena.artrip@gmail.com>
Date: Mon, 25 Apr 2016 02:14:11 -0400
Subject: [PATCH] virtualbox: obey NIX_BUILD_CORES for make invocation,
 backport to 16.03 (#14964)

---
 pkgs/applications/virtualization/virtualbox/default.nix | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pkgs/applications/virtualization/virtualbox/default.nix b/pkgs/applications/virtualization/virtualbox/default.nix
index 855694e04120..aed065fb0c3b 100644
--- a/pkgs/applications/virtualization/virtualbox/default.nix
+++ b/pkgs/applications/virtualization/virtualbox/default.nix
@@ -33,7 +33,7 @@ let
           "$mod/Module.symvers"
       fi
       INSTALL_MOD_PATH="$out" INSTALL_MOD_DIR=misc \
-      make -C "$MODULES_BUILD_DIR" DEPMOD=/do_not_use_depmod \
+      make -j $NIX_BUILD_CORES -C "$MODULES_BUILD_DIR" DEPMOD=/do_not_use_depmod \
         "M=\$(PWD)/$mod" BUILD_TYPE="${buildType}" ${action}
     done
   '';
@@ -144,7 +144,7 @@ in stdenv.mkDerivation {
 
   buildPhase = ''
     source env.sh
-    kmk BUILD_TYPE="${buildType}"
+    kmk -j $NIX_BUILD_CORES BUILD_TYPE="${buildType}"
     ${forEachModule "modules"}
   '';