pcre: 8.39 -> 8.40 + security fix

CVE-2017-7186

refs nixos/security#57 #24319

pkgs/development/libraries/pcre/default.nix

@@ -7,7 +7,7 @@ with stdenv.lib;
 assert elem variant [ null "cpp" "pcre16" "pcre32" ];
 
 let
-  version = "8.39";
+  version = "8.40";
   pname = if (variant == null) then "pcre"
     else  if (variant == "cpp") then "pcre-cpp"
     else  variant;
@@ -17,7 +17,7 @@ in stdenv.mkDerivation rec {
 
   src = fetchurl {
     url = "ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-${version}.tar.bz2";
-    sha256 = "12wyajlqx2v7dsh39ra9v9m5hibjkrl129q90bp32c28haghjn5q";
+    sha256 = "1x7lpjn7jhk0n3sdvggxrlrhab8kkfjwl7qix0ypw9nlx8lpmqh0";
   };
 
   outputs = [ "bin" "dev" "out" "doc" "man" ];
@@ -29,6 +29,8 @@ in stdenv.mkDerivation rec {
   ]
     ++ optional (variant != null) "--enable-${variant}";
 
+  patches = [ ./CVE-2017-7186.patch ];
+
   doCheck = with stdenv; !(isCygwin || isFreeBSD);
     # XXX: test failure on Cygwin
     # we are running out of stack on both freeBSDs on Hydra