diff --git a/pkgs/development/compilers/llvm/4.0/clang/default.nix b/pkgs/development/compilers/llvm/4/clang/default.nix
similarity index 95%
rename from pkgs/development/compilers/llvm/4.0/clang/default.nix
rename to pkgs/development/compilers/llvm/4/clang/default.nix
index f566cd6d21c2..5be8ffd91cf1 100644
--- a/pkgs/development/compilers/llvm/4.0/clang/default.nix
+++ b/pkgs/development/compilers/llvm/4/clang/default.nix
@@ -6,7 +6,7 @@ let
     name = "clang-${version}";
 
     unpackPhase = ''
-      unpackFile ${fetch "cfe" "1p55db1yfya60r2fnr9bh8pj8fqq5gjc1fnv0c1kmac8yfvwkmkn"}
+      unpackFile ${fetch "cfe" "1lsdyrz82vyrsc7k0ah1zmzzan61s5kakxrkxgfbmklp3pclfkwp"}
       mv cfe-${version}* clang
       sourceRoot=$PWD/clang
       unpackFile ${clang-tools-extra_src}
diff --git a/pkgs/development/compilers/llvm/4.0/clang/purity.patch b/pkgs/development/compilers/llvm/4/clang/purity.patch
similarity index 100%
rename from pkgs/development/compilers/llvm/4.0/clang/purity.patch
rename to pkgs/development/compilers/llvm/4/clang/purity.patch
diff --git a/pkgs/development/compilers/llvm/4.0/default.nix b/pkgs/development/compilers/llvm/4/default.nix
similarity index 82%
rename from pkgs/development/compilers/llvm/4.0/default.nix
rename to pkgs/development/compilers/llvm/4/default.nix
index f407b2cdc9f5..cbb3852057df 100644
--- a/pkgs/development/compilers/llvm/4.0/default.nix
+++ b/pkgs/development/compilers/llvm/4/default.nix
@@ -3,18 +3,18 @@ let
   callPackage = newScope (self // { inherit stdenv isl release_version version fetch; });
 
   release_version = "4.0.0";
-  rc = "rc2";
+  rc = "rc3";
   version = "${release_version}${rc}";
 
   fetch = name: sha256: fetchurl {
     url = "http://llvm.org/pre-releases/${release_version}/${rc}/${name}-${version}.src.tar.xz";
-    # Once 4.0 is released, use this instead:
+    # Once 4 is released, use this instead:
     # url = "http://llvm.org/releases/${release-version}/${name}-${version}.src.tar.xz";
     inherit sha256;
   };
 
-  compiler-rt_src = fetch "compiler-rt" "07i098rj41h1sq2f30d6161924zr5yd9gx5kans79p7akxxgc0jr";
-  clang-tools-extra_src = fetch "clang-tools-extra" "0ypvkv55pw88iaixib29sgz44d4pfs166vpswnrrbkqlhz92ns0z";
+  compiler-rt_src = fetch "compiler-rt" "0jfqhz95cp15c5688c6l9mr12s0qp86milpcrjlc93dc2jy08ba5";
+  clang-tools-extra_src = fetch "clang-tools-extra" "1c9c507w3f5vm153rdd0kmzvv2ski6z439izk01zf5snfwkqxkq8";
 
   self = {
     llvm = callPackage ./llvm.nix {
diff --git a/pkgs/development/compilers/llvm/4.0/libc++/default.nix b/pkgs/development/compilers/llvm/4/libc++/default.nix
similarity index 85%
rename from pkgs/development/compilers/llvm/4.0/libc++/default.nix
rename to pkgs/development/compilers/llvm/4/libc++/default.nix
index 9f950e601b21..57e064fb79ad 100644
--- a/pkgs/development/compilers/llvm/4.0/libc++/default.nix
+++ b/pkgs/development/compilers/llvm/4/libc++/default.nix
@@ -3,7 +3,7 @@
 stdenv.mkDerivation rec {
   name = "libc++-${version}";
 
-  src = fetch "libcxx" "130clvfffqml8hbnlvr596nfjk18n6ifxab27xl66nxhq99wccfn";
+  src = fetch "libcxx" "15l6bcmwczspbqcq4m2lmzb23g11axr9m8dayn25iys26nn00q43";
 
   postUnpack = ''
     unpackFile ${libcxxabi.src}
@@ -16,7 +16,7 @@ stdenv.mkDerivation rec {
   '';
 
   patchPhase = ''
-		substituteInPlace lib/CMakeLists.txt --replace "/usr/lib/libc++" "\''${LIBCXX_LIBCXXABI_LIB_PATH}/libc++"
+    substituteInPlace lib/CMakeLists.txt --replace "/usr/lib/libc++" "\''${LIBCXX_LIBCXXABI_LIB_PATH}/libc++"
   '';
 
   buildInputs = [ cmake llvm libcxxabi ] ++ lib.optional stdenv.isDarwin fixDarwinDylibNames;
diff --git a/pkgs/development/compilers/llvm/4.0/libc++/setup-hook.sh b/pkgs/development/compilers/llvm/4/libc++/setup-hook.sh
similarity index 100%
rename from pkgs/development/compilers/llvm/4.0/libc++/setup-hook.sh
rename to pkgs/development/compilers/llvm/4/libc++/setup-hook.sh
diff --git a/pkgs/development/compilers/llvm/4.0/libc++abi.nix b/pkgs/development/compilers/llvm/4/libc++abi.nix
similarity index 95%
rename from pkgs/development/compilers/llvm/4.0/libc++abi.nix
rename to pkgs/development/compilers/llvm/4/libc++abi.nix
index 362663ed443f..fc1a6d84caa8 100644
--- a/pkgs/development/compilers/llvm/4.0/libc++abi.nix
+++ b/pkgs/development/compilers/llvm/4/libc++abi.nix
@@ -3,7 +3,7 @@
 stdenv.mkDerivation {
   name = "libc++abi-${version}";
 
-  src = fetch "libcxxabi" "09hlqlbxpnqi3449nrk43khp4jgd34xwx406mw6igwl8a673pa85";
+  src = fetch "libcxxabi" "1frj1wz780xcwq77icfclnw6q4c8bkkdzkqsrmfjv9963kjylsy5";
 
   buildInputs = [ cmake ] ++ stdenv.lib.optional (!stdenv.isDarwin && !stdenv.isFreeBSD) libunwind;
 
diff --git a/pkgs/development/compilers/llvm/4.0/lld.nix b/pkgs/development/compilers/llvm/4/lld.nix
similarity index 86%
rename from pkgs/development/compilers/llvm/4.0/lld.nix
rename to pkgs/development/compilers/llvm/4/lld.nix
index 004230ca81ab..7fe08cb02625 100644
--- a/pkgs/development/compilers/llvm/4.0/lld.nix
+++ b/pkgs/development/compilers/llvm/4/lld.nix
@@ -10,7 +10,7 @@
 stdenv.mkDerivation {
   name = "lld-${version}";
 
-  src = fetch "lld" "144vmb13800s33xgd18321lrviw21mjx5dphzszjgvizn4a1sf1p";
+  src = fetch "lld" "0kmyp7iyf4f76wgy87jczkyhvzhlwfydvxgggl74z0x89xgry745";
 
   buildInputs = [ cmake llvm ];
 
diff --git a/pkgs/development/compilers/llvm/4.0/lldb.nix b/pkgs/development/compilers/llvm/4/lldb.nix
similarity index 93%
rename from pkgs/development/compilers/llvm/4.0/lldb.nix
rename to pkgs/development/compilers/llvm/4/lldb.nix
index f37e6fdfafc2..23667e6afcd7 100644
--- a/pkgs/development/compilers/llvm/4.0/lldb.nix
+++ b/pkgs/development/compilers/llvm/4/lldb.nix
@@ -17,7 +17,7 @@
 stdenv.mkDerivation {
   name = "lldb-${version}";
 
-  src = fetch "lldb" "0g3il7bz1b0xbcm85c6r64vgn8ppxigi1s39s3xzga4pkllf7k07";
+  src = fetch "lldb" "1qr0ky7llwgjgx1pzkp3pnz32nb6f7lvg8qg6rp5axhgpkx54hz7";
 
   patchPhase = ''
     # Fix up various paths that assume llvm and clang are installed in the same place
diff --git a/pkgs/development/compilers/llvm/4.0/llvm-outputs.patch b/pkgs/development/compilers/llvm/4/llvm-outputs.patch
similarity index 100%
rename from pkgs/development/compilers/llvm/4.0/llvm-outputs.patch
rename to pkgs/development/compilers/llvm/4/llvm-outputs.patch
diff --git a/pkgs/development/compilers/llvm/4.0/llvm.nix b/pkgs/development/compilers/llvm/4/llvm.nix
similarity index 97%
rename from pkgs/development/compilers/llvm/4.0/llvm.nix
rename to pkgs/development/compilers/llvm/4/llvm.nix
index d54390e5ee8d..2d36f7cd0fb1 100644
--- a/pkgs/development/compilers/llvm/4.0/llvm.nix
+++ b/pkgs/development/compilers/llvm/4/llvm.nix
@@ -21,7 +21,7 @@
 }:
 
 let
-  src = fetch "llvm" "1qfvvblca2aa5shamz66132k30hmpq2mkpfn172xzzlm6znzlmr2";
+  src = fetch "llvm" "0ic3y9gaissi6ixyj9x1c0pq69wfbl2svhprp33av0b58f7wj9v7";
   shlib = if stdenv.isDarwin then "dylib" else "so";
 
   # Used when creating a version-suffixed symlink of libLLVM.dylib
@@ -111,7 +111,7 @@ in stdenv.mkDerivation rec {
     description = "Collection of modular and reusable compiler and toolchain technologies";
     homepage    = http://llvm.org/;
     license     = stdenv.lib.licenses.ncsa;
-    maintainers = with stdenv.lib.maintainers; [ lovek323 raskin viric ];
+    maintainers = with stdenv.lib.maintainers; [ lovek323 raskin viric dtzWill ];
     platforms   = stdenv.lib.platforms.all;
   };
 }
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 3f2bfc5bda09..34341874e3a0 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -4759,7 +4759,7 @@ with pkgs;
 
   clang = llvmPackages.clang;
 
-  clang_40 = lowPrio llvmPackages_40.clang;
+  clang_4 = lowPrio llvmPackages_4.clang;
   clang_39 = llvmPackages_39.clang;
   clang_38 = llvmPackages_38.clang;
   clang_37 = llvmPackages_37.clang;
@@ -5314,13 +5314,13 @@ with pkgs;
 
   lizardfs = callPackage ../tools/filesystems/lizardfs { };
 
-  lld = lowPrio llvmPackages_40.lld;
+  lld = lowPrio llvmPackages_4.lld;
 
   lldb = llvmPackages.lldb;
 
   llvm = llvmPackages.llvm;
 
-  llvm_40 = lowPrio llvmPackages_40.llvm;
+  llvm_4 = lowPrio llvmPackages_4.llvm;
   llvm_39 = llvmPackages_39.llvm;
   llvm_38 = llvmPackages_38.llvm;
   llvm_37 = llvmPackages_37.llvm;
@@ -5358,7 +5358,7 @@ with pkgs;
     inherit (stdenvAdapters) overrideCC;
   };
 
-  llvmPackages_40 = callPackage ../development/compilers/llvm/4.0 {
+  llvmPackages_4 = callPackage ../development/compilers/llvm/4 {
     inherit (stdenvAdapters) overrideCC;
   };