diff --git a/pkgs/os-specific/linux/mdadm/4.nix b/pkgs/os-specific/linux/mdadm/4.nix
index 05d98de0b23..a83e7c852ee 100644
--- a/pkgs/os-specific/linux/mdadm/4.nix
+++ b/pkgs/os-specific/linux/mdadm/4.nix
@@ -1,4 +1,7 @@
-{ stdenv, fetchurl, groff }:
+{ stdenv
+, fetchurl, groff
+, buildPlatform, hostPlatform
+}:
 
 assert stdenv.isLinux;
 
@@ -19,8 +22,8 @@ stdenv.mkDerivation rec {
   makeFlags = [
     "NIXOS=1" "INSTALL=install" "INSTALL_BINDIR=$(out)/sbin"
     "MANDIR=$(out)/share/man" "RUN_DIR=/dev/.mdadm"
-  ] ++ stdenv.lib.optionals (stdenv ? cross) [
-    "CROSS_COMPILE=${stdenv.cross.config}-"
+  ] ++ stdenv.lib.optionals (hostPlatform != buildPlatform) [
+    "CROSS_COMPILE=${stdenv.cc.prefix}"
   ];
 
   nativeBuildInputs = [ groff ];
diff --git a/pkgs/os-specific/linux/mdadm/default.nix b/pkgs/os-specific/linux/mdadm/default.nix
index e0109791ef2..589099c911c 100644
--- a/pkgs/os-specific/linux/mdadm/default.nix
+++ b/pkgs/os-specific/linux/mdadm/default.nix
@@ -1,4 +1,7 @@
-{ stdenv, fetchurl, groff }:
+{ stdenv
+, fetchurl, groff
+, buildPlatform, hostPlatform
+}:
 
 assert stdenv.isLinux;
 
@@ -19,8 +22,8 @@ stdenv.mkDerivation rec {
   makeFlags = [
     "NIXOS=1" "INSTALL=install" "INSTALL_BINDIR=$(out)/sbin"
     "MANDIR=$(out)/share/man" "RUN_DIR=/dev/.mdadm"
-  ] ++ stdenv.lib.optionals (stdenv ? cross) [
-    "CROSS_COMPILE=${stdenv.cross.config}-"
+  ] ++ stdenv.lib.optionals (hostPlatform != buildPlatform) [
+    "CROSS_COMPILE=${stdenv.cc.prefix}"
   ];
 
   nativeBuildInputs = [ groff ];