guix: build: Add "share/pkgconfig" to PKG_CONFIG_PATH, as used by xorg.

* guix/build/gnu-build-system.scm (set-paths): Add "share/pkgconfig"
     to PKG_CONFIG_PATH.

gnu: Add cross tool chain.

* gnu/packages/cross-base.scm: New file.
* gnu/packages/patches/gcc-cross-environment-variables.patch: New file.
* Makefile.am (MODULES): Add cross-base.scm.
  (dist_patch_DATA): Add gcc-cross-environment-variables.patch.
* gnu/packages/base.scm (gcc-4.7): Use `LDFLAGS_FOR_TARGET' instead of
  `LDFLAGS_FOR_BUILD', and use `-B' instead of `-L'.
* gnu/packages/bootstrap.scm (glibc-dynamic-linker): Add case for
  "mips64el-linux".

gnu: linux: Make `system->linux-architecture' public, and add ARM.

* gnu/packages/linux.scm (system->linux-architecture): Make public.  Add
  "arm".

gnu: linux-libre-headers: Set 'ARCH' to 'mips'.

* gnu/packages/linux.scm (system->linux-architecture): New procedure.
  (linux-libre-headers): Adjust accordingly.

gnu: gcc: Remove extraneous newline in 'LIB_SPEC'.

* gnu/packages/base.scm (gcc-4.7): Remove trailing newline when patching
  'LIB_SPEC'.

pull: Distinguish "already up to date" from "updated".

* guix/ui.scm (show-what-to-build): Return (length req*).
* guix/scripts/pull.scm (guix-pull): Print an "already up to date"
  message when there's nothing to build.

pull: Build (guix build download) first, because of the (gnutls) autoload.

* guix/scripts/pull.scm (unpack): Build (guix build download) first, as
  done in 855a8ad71def2ebc594ed32c57bda0ca4e13d91c.
  Reported by Andreas Enge <andreas@enge.fr>.

guix: Make sure UPDATES-DIR is valid.

* scripts/guix.in: Make sure UPDATES-DIR is not #f.

Add "guix pull".

* guix/scripts/pull.scm: New file.
* Makefile.am (MODULES): Add it.
* doc/guix.texi (Invoking guix pull): New node.
  (Invoking guix package): Add cross-ref to it.
* guix/ui.scm (config-directory): New procedure.
* scripts/guix.in: When `GUIX_UNINSTALLED' is undefined, add
  $XDG_CONFIG_HOME/guix/latest to the search path.
* po/POTFILES.in: Add guix/scripts/pull.scm.

ui: Factorize `show-what-to-build'.

* guix/scripts/package.scm (guix-package)[show-what-to-build]: Move to..
* guix/ui.scm (show-what-to-build): ... here.  Add a `store'
  parameter'.  Adjust callers.
* guix/scripts/build.scm (guix-build): Use it.  Remove `req' and `req*'
  variables.

build: Adjust guix.texi to Texinfo 5.0.

* doc/guix.texi: Change @title and @subtitle syntax to please Texinfo 5.0.

ui: Add temporary file handling and atomic symlink switch.

* guix/scripts/download.scm (call-with-temporary-output-file): Move to
  ui.scm.
* guix/scripts/package.scm (switch-symlinks): Likewise.
* guix/ui.scm (call-with-temporary-output-file, switch-symlinks): New
  procedures.

download: Adjust to `http-get*' deprecation.

* guix/build/download.scm (http-fetch): Adjust to use #:streaming? when
  using Guile 2.0.8+.

derivations: Add a search path parameter for module derivations.

* guix/derivations.scm (imported-modules, compiled-modules): Add a
  `module-path' parameter.  Use it instead of %LOAD-PATH.

gnu: texinfo: Make Perl a propagated input.

* gnu/packages/texinfo.scm (texinfo): Make PERL a propagated input.

build: Add missing -I flag for the daemon.

* daemon.am (libstore_a_CPPFLAGS): Add missing -I, for schema.sql.hh.

daemon: Add `--listen'.

* nix/nix-daemon/guix-daemon.cc (GUIX_OPT_LISTEN): New macro.
  (options): Add `--listen'.
  (parse_opt): Handle it.
* doc/guix.texi (Invoking guix-daemon): Mention it.

Update from upstream Nix.

store: Add the `%daemon-socket-file' parameter.

* guix/store.scm (%daemon-socket-file): New variable.
  (open-connection): Use it as the default value for FILE.

Add Mark to `AUTHORS'.