diff --git a/pkgs/by-name/rp/rpcemu/package.nix b/pkgs/by-name/rp/rpcemu/package.nix
index 50e1ea55d587..58d6335f2c0e 100644
--- a/pkgs/by-name/rp/rpcemu/package.nix
+++ b/pkgs/by-name/rp/rpcemu/package.nix
@@ -12,6 +12,8 @@ stdenv.mkDerivation (finalAttrs: {
   pname = "rpcemu";
   version = "0.9.5";
 
+  env.NIX_CFLAGS_COMPILE = "-std=gnu17";
+
   src = fetchhg {
     url = "http://www.home.marutan.net/hg/rpcemu";
     rev = "release_${finalAttrs.version}";