diff --git a/pkgs/development/tools/parsing/flexc++/default.nix b/pkgs/development/tools/parsing/flexc++/default.nix
index e1426b3a1d4..4fef3731962 100644
--- a/pkgs/development/tools/parsing/flexc++/default.nix
+++ b/pkgs/development/tools/parsing/flexc++/default.nix
@@ -2,10 +2,10 @@
 
 stdenv.mkDerivation rec {
   name = "flexc++-${version}";
-  version = "2.03.00";
+  version = "2.04.00";
 
   src = fetchFromGitHub {
-    sha256 = "1knb5h6l71n5zi9xzml5f6v7wspbk7vrcaiy2div8bnj7na3z717";
+    sha256 = "0fz9gxpc491cngj9z9y059vbl65ng48c4nw9k3sl983zfnqfy26y";
     rev = version;
     repo = "flexcpp";
     owner = "fbb-git";