diff --git a/pkgs/tools/graphics/icoutils/default.nix b/pkgs/tools/graphics/icoutils/default.nix
index 8c50ffdce62e..1806699b1c23 100644
--- a/pkgs/tools/graphics/icoutils/default.nix
+++ b/pkgs/tools/graphics/icoutils/default.nix
@@ -21,9 +21,8 @@ stdenv.mkDerivation rec {
   buildInputs = [ libpng perl ];
   propagatedBuildInputs = [ perlPackages.LWP ];
 
-  # Fixes a build failure on aarch64-darwin. Define for all Darwin targets for when x86_64-darwin
-  # upgrades to a newer SDK.
-  env.NIX_CFLAGS_COMPILE = lib.optionalString stdenv.hostPlatform.isDarwin "-DTARGET_OS_IPHONE=0";
+  # Fixes build failures on Darwin. These should be defined in `TargetConditional.h`, but it’s failing anyway.
+  env.NIX_CFLAGS_COMPILE = lib.optionalString stdenv.hostPlatform.isDarwin "-DTARGET_OS_IPHONE=0 -DTARGET_OS_EMBEDDED=0";
 
   postPatch = ''
     patchShebangs extresso/extresso