diff --git a/pkgs/tools/networking/whois/clang.patch b/pkgs/tools/networking/whois/clang.patch
deleted file mode 100644
index 3091b9a3eee3..000000000000
--- a/pkgs/tools/networking/whois/clang.patch
+++ /dev/null
@@ -1,11 +0,0 @@
---- 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 465ab7650137..fe4950d5c240 100644
--- a/pkgs/tools/networking/whois/default.nix
+++ b/pkgs/tools/networking/whois/default.nix
@@ -1,20 +1,16 @@
 { lib, stdenv, fetchFromGitHub, perl, gettext, pkg-config, libidn2, libiconv }:
 
 stdenv.mkDerivation rec {
-  version = "5.5.19";
+  version = "5.5.20";
   pname = "whois";
 
   src = fetchFromGitHub {
     owner = "rfc1036";
     repo = "whois";
     rev = "v${version}";
-    hash = "sha256-4mFn5cY7ipAU4vOiHC2s69fxYJwShQEQ1eA8t5JvOP0=";
+    hash = "sha256-0vQ6GBBtNA6Phlqhl3NZvEJqoyZ1um7VdkpsIRKhsm4=";
   };
 
-  patches = [
-    ./clang.patch
-  ];
-
   nativeBuildInputs = [ perl gettext pkg-config ];
   buildInputs = [ libidn2 libiconv ];