fetchurl: Remove some compatibility hacks

pkgs/build-support/fetchurl/builder.sh

@@ -29,20 +29,6 @@ tryDownload() {
 
 
 finish() {
-    # On old versions of Nix, verify the hash of the output.  On newer
-    # versions, Nix verifies the hash itself.
-    if test "$NIX_OUTPUT_CHECKED" != "1"; then
-        if test "$outputHashAlgo" != "md5"; then
-            echo "hashes other than md5 are unsupported in Nix <= 0.7, upgrade to Nix 0.8"
-            exit 1
-        fi
-        actual=$(md5sum -b "$out" | cut -c1-32)
-        if test "$actual" != "$id"; then
-            echo "hash is $actual, expected $id"
-            exit 1
-        fi
-    fi
-
     stopNest
     exit 0
 }

pkgs/build-support/fetchurl/default.nix

@@ -17,10 +17,7 @@ let
 
   # Names of the master sites that are mirrored (i.e., "sourceforge",
   # "gnu", etc.).
-  sites =
+  sites = builtins.attrNames mirrors;
-    if builtins ? attrNames
-    then builtins.attrNames mirrors
-    else [] /* backwards compatibility */;
 
   impureEnvVars = [
     # We borrow these environment variables from the caller to allow
@@ -90,9 +87,6 @@ stdenv.mkDerivation {
   # (http://nixos.org/tarballs) over the original URLs.
   preferHashedMirrors = true;
 
-  # Compatibility with Nix <= 0.7.
-  id = md5;
-
   # New-style output content requirements.
   outputHashAlgo = if outputHashAlgo != "" then outputHashAlgo else
       if sha256 != "" then "sha256" else if sha1 != "" then "sha1" else "md5";