diff --git a/pkgs/tools/networking/whois/clang.patch b/pkgs/tools/networking/whois/clang.patch
new file mode 100644
index 000000000000..3091b9a3eee3
--- /dev/null
+++ b/pkgs/tools/networking/whois/clang.patch
@@ -0,0 +1,11 @@
+--- a/utils.h
++++ b/utils.h
+@@ -15,7 +15,7 @@
+ #endif
+ 
+ /* Portability macros */
+-#ifdef __GNUC__
++#if defined __GNUC__ && ! defined __clang__
+ # define NORETURN __attribute__((noreturn))
+ # define MALLOC_FREE __attribute__((malloc(free)))
+ # define NONNULL __attribute__((returns_nonnull))
diff --git a/pkgs/tools/networking/whois/default.nix b/pkgs/tools/networking/whois/default.nix
index f9d2e90b58e4..465ab7650137 100644
--- a/pkgs/tools/networking/whois/default.nix
+++ b/pkgs/tools/networking/whois/default.nix
@@ -11,6 +11,10 @@ stdenv.mkDerivation rec {
     hash = "sha256-4mFn5cY7ipAU4vOiHC2s69fxYJwShQEQ1eA8t5JvOP0=";
   };
 
+  patches = [
+    ./clang.patch
+  ];
+
   nativeBuildInputs = [ perl gettext pkg-config ];
   buildInputs = [ libidn2 libiconv ];