diff --git a/pkgs/development/libraries/libaom/default.nix b/pkgs/development/libraries/libaom/default.nix
index c5e40babfd67..30d3c0d81b55 100644
--- a/pkgs/development/libraries/libaom/default.nix
+++ b/pkgs/development/libraries/libaom/default.nix
@@ -50,7 +50,7 @@ stdenv.mkDerivation rec {
     # CPU detection isn't supported on Darwin and breaks the aarch64-darwin build:
     "-DCONFIG_RUNTIME_CPU_DETECT=0"
   ] ++ lib.optionals (isCross && !stdenv.hostPlatform.isx86) [
-    "-DAS_EXECUTABLE=${stdenv.cc.targetPrefix}as"
+    "-DCMAKE_ASM_COMPILER=${stdenv.cc.targetPrefix}as"
   ] ++ lib.optionals stdenv.isAarch32 [
     # armv7l-hf-multiplatform does not support NEON
     # see lib/systems/platform.nix