gnu: Add llvm and clang.

* gnu/packages/llvm.scm: New file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.

gnu-system.am

@@ -161,6 +161,7 @@ GNU_SYSTEM_MODULES =				\
   gnu/packages/links.scm			\
   gnu/packages/linux.scm			\
   gnu/packages/lisp.scm				\
+  gnu/packages/llvm.scm				\
   gnu/packages/lout.scm				\
   gnu/packages/lsh.scm				\
   gnu/packages/lsof.scm				\

gnu/packages/llvm.scm

@@ -0,0 +1,107 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2014 Eric Bavier <bavier@member.fsf.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 llvm)
+  #:use-module (guix packages)
+  #:use-module (guix licenses)
+  #:use-module (guix download)
+  #:use-module (guix utils)
+  #:use-module (guix build-system gnu)
+  #:use-module (guix build-system cmake)
+  #:use-module (gnu packages)
+  #:use-module (gnu packages perl)
+  #:use-module (gnu packages python)
+  #:use-module (gnu packages xml))
+
+(define-public llvm
+  (package
+    (name "llvm")
+    (version "3.5.0")
+    (source
+     (origin
+      (method url-fetch)
+      (uri (string-append "http://llvm.org/releases/"
+                          version "/llvm-" version ".src.tar.xz"))
+      (sha256
+       (base32
+        "00swb43mzlvda8306arlg2jw7g6k3acwfccgf1k4c2pgd3rrkq98"))))
+    (build-system cmake-build-system)
+    (native-inputs
+     `(("python" ,python-wrapper)
+       ("perl"   ,perl)))
+    (arguments
+     `(#:phases (alist-cons-before
+                 'build 'link-lib-for-build-exec
+                 (lambda* (#:key outputs #:allow-other-keys)
+                   ;; This is a hacky fix that will allow binaries to run
+                   ;; before being installed.  -DCMAKE_SKIP_BUILD_RPATH=FALSE
+                   ;; seems to not help.  Nixpkgs does the same.
+                   (let* ((out       (assoc-ref outputs "out"))
+                          (out-lib   (string-append out "/lib"))
+                          (build-lib (string-append (getcwd) "/lib")))
+                     (mkdir-p out)
+                     (symlink build-lib out-lib)))
+                 (alist-cons-after
+                  'build 'cleanup-out
+                  (lambda* (#:key outputs #:allow-other-keys)
+                    ;; Cleanup the symlink that was created previously.  Let
+                    ;; the install phase repopulate out.
+                    (delete-file-recursively (assoc-ref outputs "out")))
+                  %standard-phases))))
+    (home-page "http://www.llvm.org")
+    (synopsis "Optimizing compiler infrastructure")
+    (description
+     "LLVM is a compiler infrastructure designed for compile-time, link-time, runtime,
+and idle-time optimization of programs from arbitrary programming languages.
+It currently supports compilation of C and C++ programs, using front-ends
+derived from GCC 4.0.1.  A new front-end for the C family of languages is in
+development.  The compiler infrastructure includes mirror sets of programming
+tools as well as libraries with equivalent functionality.")
+    (license ncsa)))
+
+(define-public clang
+  (package
+    (name "clang")
+    (version (package-version llvm))
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append "http://llvm.org/releases/"
+                           version "/cfe-" version ".src.tar.xz"))
+       (sha256
+        (base32
+         "12yv3jwdjcbkrx7zjm8wh4jrvb59v8fdw4mnmz3zc1jb00p9k07w"))))
+    ;; Using cmake allows us to treat llvm as an external library.  There
+    ;; doesn't seem to be any way to do this with clang's autotools-based
+    ;; build system.
+    (build-system cmake-build-system)
+    (native-inputs (package-native-inputs llvm))
+    (inputs
+     `(("libxml2" ,libxml2)
+       ,@(package-inputs llvm)))
+    (propagated-inputs
+     `(("llvm" ,llvm)))
+    (arguments `(#:configure-flags '("-DCLANG_INCLUDE_TESTS=True")))
+    (home-page "http://clang.llvm.org")
+    (synopsis "C language family frontend for LLVM")
+    (description
+     "Clang is a compiler front end for the C, C++, Objective-C and
+Objective-C++ programming languages.  It uses LLVM as its back end.  The Clang
+project includes the Clang front end, the Clang static analyzer, and several
+code analysis tools.")
+    (license ncsa)))