From d0abf829a95b5a4501eae452e03ca8b1d47b0b16 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= <ludo@gnu.org>
Date: Fri, 19 Jun 2015 11:34:16 +0200
Subject: [PATCH] gnu: Add libstdc++ as a standalone package.

* gnu/packages/gcc.scm (make-libstdc++): New procedure.
  (libstdc++-4.9): New variable.
* gnu/packages/commencement.scm (libstdc++): Add TODO comment.
---
 gnu/packages/commencement.scm |  1 +
 gnu/packages/gcc.scm          | 26 ++++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/gnu/packages/commencement.scm b/gnu/packages/commencement.scm
index a5402f0556..9cabaa0886 100644
--- a/gnu/packages/commencement.scm
+++ b/gnu/packages/commencement.scm
@@ -497,6 +497,7 @@ exec ~a/bin/~a-~a -B~a/lib -Wl,-dynamic-linker -Wl,~a/~a \"$@\"~%"
 (define libstdc++
   ;; Intermediate libstdc++ that will allow us to build the final GCC
   ;; (remember that GCC-BOOT0 cannot build libstdc++.)
+  ;; TODO: Write in terms of 'make-libstdc++'.
   (package-with-bootstrap-guile
    (package (inherit gcc-4.8)
      (name "libstdc++")
diff --git a/gnu/packages/gcc.scm b/gnu/packages/gcc.scm
index b652521bb8..73e8ae97e8 100644
--- a/gnu/packages/gcc.scm
+++ b/gnu/packages/gcc.scm
@@ -347,6 +347,32 @@ Go.  It also includes runtime support libraries for these languages.")
                             '("gcc-arm-link-spec-fix.patch"
                               "gcc-5.0-libvtv-runpath.patch")))))))
 
+(define-public (make-libstdc++ gcc)
+  "Return a libstdc++ package based on GCC.  The primary use case is when
+using compilers other than GCC."
+  (package
+    (inherit gcc)
+    (name "libstdc++")
+    (arguments
+     `(#:out-of-source? #t
+       #:phases (alist-cons-before
+                 'configure 'chdir
+                 (lambda _
+                   (chdir "libstdc++-v3"))
+                 %standard-phases)
+       #:configure-flags `("--disable-libstdcxx-pch"
+                           ,(string-append "--with-gxx-include-dir="
+                                           (assoc-ref %outputs "out")
+                                           "/include"))))
+    (outputs '("out" "debug"))
+    (inputs '())
+    (native-inputs '())
+    (propagated-inputs '())
+    (synopsis "GNU C++ standard library")))
+
+(define-public libstdc++-4.9
+  (make-libstdc++ gcc-4.9))
+
 (define* (custom-gcc gcc name languages #:key (separate-lib-output? #t))
   "Return a custom version of GCC that supports LANGUAGES."
   (package (inherit gcc)