diff --git a/pkgs/applications/science/logic/why3/default.nix b/pkgs/applications/science/logic/why3/default.nix
index d1fb853ee9e1..0313467ed789 100644
--- a/pkgs/applications/science/logic/why3/default.nix
+++ b/pkgs/applications/science/logic/why3/default.nix
@@ -1,12 +1,12 @@
-{ fetchurl, stdenv, ocaml, ocamlPackages, coq }:
+{ fetchurl, stdenv, ocamlPackages, coq }:
 
 stdenv.mkDerivation rec {
   name    = "why3-${version}";
-  version = "0.86.1";
+  version = "0.86.2";
 
   src = fetchurl {
-    url    = https://gforge.inria.fr/frs/download.php/file/34797/why3-0.86.1.tar.gz;
-    sha256 = "129kzq79n8h480zrlphgh1ixvwp3wm18nbcky9bp4wdnr6zaibd7";
+    url    = https://gforge.inria.fr/frs/download.php/file/35214/why3-0.86.2.tar.gz;
+    sha256 = "08sa7dmp6yp29xn0m6h98nic4q47vb4ahvaid5drwh522pvwvg10";
   };
 
   buildInputs = with ocamlPackages;