Merge branch 'master' into staging-next

There ver very many conflicts, basically all due to
name -> pname+version.  Fortunately, almost everything was auto-resolved
by kdiff3, and for now I just fixed up a couple evaluation problems,
as verified by the tarball job.  There might be some fallback to these
conflicts, but I believe it should be minimal.

Hydra nixpkgs: ?compare=1538299

pkgs/development/libraries/liburing/default.nix

@@ -1,16 +1,57 @@
 { stdenv, fetchgit
+, fetchpatch
 }:
 
 stdenv.mkDerivation rec {
   pname = "liburing";
-  version = "1.0.0pre156_${builtins.substring 0 7 src.rev}";
+  version = "0.1";
 
   src = fetchgit {
     url    = "http://git.kernel.dk/liburing";
-    rev    = "c31c7ec4bcd7bb0d7b28897d730431c02b9d4ea1";
-    sha256 = "17d6s03fyajcrijca9d2d6llbf8cl8dyalpxnl39az3452p04s11";
+    rev    = "refs/tags/liburing-${version}";
+    sha256 = "038iqsbm9bdmlwvmb899bc6g1rw5dalr990azynbvgn8qs5adysh";
   };
 
+  patches = [
+
+    # This patch re-introduces support for aarch64-linux, by adding the
+    # necessary memory barrier primitives for it to work.
+    #
+    # Already upstream: remove when moving to the next version
+    (fetchpatch {
+      url    = "http://git.kernel.dk/cgit/liburing/patch/?id=0520db454c29f1d96cda6cf6cedeb93df65301e8";
+      sha256 = "1i8133sb1imzxpplmhlhnaxkffgplhj40vanivc6clbibvhgwpq6";
+    })
+
+    # This patch shuffles the name of the io_uring memory barrier primitives.
+    # They were using extremely common names by accident, which caused
+    # namespace conflicts with many other projects using the same names. Note:
+    # this does not change the user-visible API of liburing (liburing is
+    # designed exactly to hide the necessary memory barriers when using the
+    # io_uring syscall directly). It only changes the names of some internals.
+    # The only reason this caused problems at all is because memory barrier
+    # primitives are written as preprocessor defines, in a common header file,
+    # which get included unilaterally.
+    #
+    # Already upstream: remove when moving to the next version
+    (fetchpatch {
+      url    = "http://git.kernel.dk/cgit/liburing/patch/?id=552c6a08d04c74d20eeaa86f535bfd553b352370";
+      sha256 = "123d6jdqfy7b8aq9f6ax767n48hhbx6pln3nlrp623595i8zz3wf";
+    })
+
+    # Finally, this patch fixes the aarch64-linux support introduced by the
+    # first patch, but which was _broken_ by the second patch, in a horrid
+    # twist of fate: it neglected to change the names of the aarch64 barriers
+    # appropriately.
+    #
+    # Already upstream: remove when moving to the next version
+    (fetchpatch {
+      url    = "http://git.kernel.dk/cgit/liburing/patch/?id=6e9dd0c8c50b5988a0c77532c9c2bd6afd4790d2";
+      sha256 = "11mqa1bp2pdfqh08gpcd98kg7lh3rrng41b4l1wvhxdbvg5rfw9c";
+    })
+
+  ];
+
   separateDebugInfo = true;
   enableParallelBuilding = true;