diff --git a/pkgs/development/libraries/x265/default.nix b/pkgs/development/libraries/x265/default.nix
index 6eacb730a544..9f3f97b1bc57 100644
--- a/pkgs/development/libraries/x265/default.nix
+++ b/pkgs/development/libraries/x265/default.nix
@@ -96,13 +96,13 @@ stdenv.mkDerivation rec {
       ${mkFlag (!stdenv.hostPlatform.isStatic) "ENABLE_SHARED"}
       -DHIGH_BIT_DEPTH=OFF
       -DENABLE_HDR10_PLUS=ON
-      ${mkFlag (isCross && stdenv.hostPlatform.isAarch32) "CROSS_COMPILE_ARM"}
       ${mkFlag cliSupport "ENABLE_CLI"}
       ${mkFlag unittestsSupport "ENABLE_TESTS"}
     )
   '' + lib.optionalString isCross ''
     cmakeFlagsArray+=(
-      ${mkFlag (isCross && stdenv.hostPlatform.isAarch64) "CROSS_COMPILE_ARM64"}
+      ${mkFlag (stdenv.hostPlatform.isAarch32) "CROSS_COMPILE_ARM"}
+      ${mkFlag (stdenv.hostPlatform.isAarch64) "CROSS_COMPILE_ARM64"}
     )
   '';