valgrind: 3.18.1 -> 3.19.0

Added trivial update script.
Dropped upstreamed rawmemchr patch.

changelog: https://valgrind.org/docs/manual/dist.news.html

pkgs/development/tools/analysis/valgrind/default.nix

@@ -1,26 +1,18 @@
 { lib, stdenv, fetchurl, fetchpatch
 , autoreconfHook, perl
 , gdb, cctools, xnu, bootstrap_cmds
+, writeScript
 }:
 
 stdenv.mkDerivation rec {
   pname = "valgrind";
-  version = "3.18.1";
+  version = "3.19.0";
 
   src = fetchurl {
     url = "https://sourceware.org/pub/${pname}/${pname}-${version}.tar.bz2";
-    sha256 = "sha256-AIWaoTp3Lt33giIl9LRu4NOa++Bx0yd42k2ZmECB9/U=";
+    sha256 = "sha256-3V40SG8aSD/3vnMAzBa01rJGkJh4d8MnjXl1NNZzjwI=";
   };
 
-  patches = [
-    # Fix tests on Musl.
-    # https://bugs.kde.org/show_bug.cgi?id=445300
-    (fetchpatch {
-      url = "https://bugsfiles.kde.org/attachment.cgi?id=143535";
-      sha256 = "036zyk30rixjvpylw3c7n171n4gpn6zcp7h6ya2dz4h5r478l9i6";
-    })
-  ];
-
   outputs = [ "out" "dev" "man" "doc" ];
 
   hardeningDisable = [ "pie" "stackprotector" ];
@@ -59,9 +51,6 @@ stdenv.mkDerivation rec {
         --replace /usr/bin/ld ${cctools}/bin/ld
     '');
 
-  # To prevent rebuild on linux when moving darwin's postPatch fixes to preConfigure
-  postPatch = "";
-
   configureFlags =
     lib.optional (stdenv.hostPlatform.system == "x86_64-linux" || stdenv.hostPlatform.system == "x86_64-darwin") "--enable-only64bit"
     ++ lib.optional stdenv.hostPlatform.isDarwin "--with-xcodedir=${xnu}/include";
@@ -77,6 +66,21 @@ stdenv.mkDerivation rec {
     done
   '';
 
+  passthru = {
+    updateScript = writeScript "update-valgrind" ''
+      #!/usr/bin/env nix-shell
+      #!nix-shell -i bash -p curl pcre common-updater-scripts
+
+      set -eu -o pipefail
+
+      # Expect the text in format of:
+      #  'Current release: <a href="/downloads/current.html#current">valgrind-3.19.0</a>'
+      new_version="$(curl -s https://valgrind.org/ |
+          pcregrep -o1 'Current release: .*>valgrind-([0-9.]+)</a>')"
+      update-source-version ${pname} "$new_version"
+    '';
+  };
+
   meta = {
     homepage = "http://www.valgrind.org/";
     description = "Debugging and profiling tool suite";