diff --git a/pkgs/by-name/st/stormlib/package.nix b/pkgs/by-name/st/stormlib/package.nix
index 76d80d9e94d2..d55b93ca48ca 100644
--- a/pkgs/by-name/st/stormlib/package.nix
+++ b/pkgs/by-name/st/stormlib/package.nix
@@ -25,6 +25,11 @@ stdenv.mkDerivation rec {
   buildInputs = [ bzip2 libtomcrypt zlib ] ++
     lib.optionals stdenv.isDarwin [ darwin.apple_sdk.frameworks.Carbon ];
 
+  env.NIX_CFLAGS_COMPILE = toString (lib.optionals stdenv.cc.isClang [
+    "-Wno-implicit-function-declaration"
+    "-Wno-int-conversion"
+  ]);
+
   meta = with lib; {
     homepage = "https://github.com/ladislav-zezula/StormLib";
     license = licenses.mit;