gnu: Add libunwind.

* gnu/packages/libunwind.scm: New file.
* Makefile.am (MODULES): Add it.

Makefile.am

@@ -101,6 +101,7 @@ MODULES =					\
   gnu/packages/libtiff.scm			\
   gnu/packages/libunistring.scm			\
   gnu/packages/libusb.scm			\
+  gnu/packages/libunwind.scm			\
   gnu/packages/linux.scm			\
   gnu/packages/lout.scm				\
   gnu/packages/lsh.scm				\

gnu/packages/libunwind.scm

@@ -0,0 +1,52 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2013 Ludovic Courtès <ludo@gnu.org>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu packages libunwind)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix build-system gnu)
+  #:use-module (guix licenses))
+
+(define-public libunwind
+  (package
+    (name "libunwind")
+    (version "1.1")
+    (source (origin
+             (method url-fetch)
+             (uri (string-append "mirror://savannah/libunwind/libunwind-"
+                                 version ".tar.gz"))
+             (sha256
+              (base32
+               "16nhx2pahh9d62mvszc88q226q5lwjankij276fxwrm8wb50zzlx"))))
+    (build-system gnu-build-system)
+    (arguments
+     ;; FIXME: As of glibc 2.17, we get 3 out of 34 test failures.
+     ;; Report them upstream.
+     '(#:tests? #f))
+    (home-page "http://www.nongnu.org/libunwind")
+    (synopsis
+     "A portable and efficient API to determine the call-chain of a program")
+    (description
+     "The primary goal of this project is to define a portable and efficient C
+programming interface (API) to determine the call-chain of a program.  The API
+additionally provides the means to manipulate the preserved (callee-saved)
+state of each call-frame and to resume execution at any point in the
+call-chain (non-local goto).  The API supports both local (same-process) and
+remote (across-process) operation.  As such, the API is useful in a number of
+applications.")
+    (license x11)))