From 52f4dd95d4c34fbf6b95e61e846002a11fc3e093 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= <ludo@gnu.org>
Date: Wed, 11 Apr 2012 16:38:21 +0000
Subject: [PATCH] GMP 5.0.3: Fix FreeBSD builds.

svn path=/nixpkgs/trunk/; revision=33748
---
 pkgs/development/libraries/gmp/5.0.3.nix | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/libraries/gmp/5.0.3.nix b/pkgs/development/libraries/gmp/5.0.3.nix
index 8c3d24d2d11..dbc9e83ed8d 100644
--- a/pkgs/development/libraries/gmp/5.0.3.nix
+++ b/pkgs/development/libraries/gmp/5.0.3.nix
@@ -1,6 +1,6 @@
 { stdenv, fetchurl, m4, cxx ? true }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (rec {
   name = "gmp-5.0.3";
 
   src = fetchurl {
@@ -51,3 +51,21 @@ stdenv.mkDerivation rec {
     platforms = stdenv.lib.platforms.all;
   };
 }
+
+//
+
+(if stdenv.isFreeBSD
+ then {
+   # On FreeBSD, GMP's `config.guess' detects the sub-architecture (e.g.,
+   # "k8") and generates code specific to that sub-architecture, in spite of
+   # `--enable-fat', leading to illegal instructions and similar errors on
+   # machines with a different sub-architecture.
+   # See <http://hydra.nixos.org/build/2269915/nixlog/1/raw>, for an example.
+   # Thus, use GNU's standard `config.guess' so that it assumes the generic
+   # architecture (e.g., "x86_64").
+   preConfigure =
+     '' rm config.guess && ln -s configfsf.guess config.guess
+        chmod +x configfsf.guess.
+     '';
+ }
+ else { }))