From 26dc84f99a8c2dfb7d00879bebff3e6324cc1944 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= <ludo@gnu.org>
Date: Fri, 18 Sep 2009 14:30:10 +0000
Subject: [PATCH] BDW-GC: Tentative fix for Cygwin.

svn path=/nixpkgs/trunk/; revision=17249
---
 .../boehm-gc/cygwin-pthread-dl.patch          | 24 +++++++++++++++++++
 .../libraries/boehm-gc/default.nix            |  4 ++++
 2 files changed, 28 insertions(+)
 create mode 100644 pkgs/development/libraries/boehm-gc/cygwin-pthread-dl.patch

diff --git a/pkgs/development/libraries/boehm-gc/cygwin-pthread-dl.patch b/pkgs/development/libraries/boehm-gc/cygwin-pthread-dl.patch
new file mode 100644
index 000000000000..9515dc237d3f
--- /dev/null
+++ b/pkgs/development/libraries/boehm-gc/cygwin-pthread-dl.patch
@@ -0,0 +1,24 @@
+Don't pass "-lpthread -ldl" on Cygwin.  See
+http://thread.gmane.org/gmane.comp.programming.garbage-collection.boehmgc/3219
+for details.
+
+--- gc-7.1/configure	2008-05-04 02:52:50.000000000 +0200
++++ gc-7.1/configure	2009-09-18 16:23:30.000000000 +0200
+@@ -4859,7 +4859,7 @@
+ 	cat >>confdefs.h <<\_ACEOF
+ #define THREAD_LOCAL_ALLOC 1
+ _ACEOF
+-
++	THREADDLLIBS=""
+ 	win32_threads=true
+ 	;;
+      *-*-darwin*)
+@@ -5934,6 +5934,7 @@
+ # dyld calls anyway
+ case "$host" in
+   *-*-darwin*) ;;
++  *-*-cygwin*) ;;
+   *)
+     { echo "$as_me:$LINENO: checking for dlopen in -ldl" >&5
+ echo $ECHO_N "checking for dlopen in -ldl... $ECHO_C" >&6; }
+
diff --git a/pkgs/development/libraries/boehm-gc/default.nix b/pkgs/development/libraries/boehm-gc/default.nix
index e793a56ed5f6..6100efe6daab 100644
--- a/pkgs/development/libraries/boehm-gc/default.nix
+++ b/pkgs/development/libraries/boehm-gc/default.nix
@@ -9,6 +9,10 @@ stdenv.mkDerivation {
     sha256 = "0c5zrsdw0rsli06lahcqwwz0prgah340fhfg7ggfgvz3iw1gdkp3";
   };
 
+  patches =
+    stdenv.lib.optional (stdenv.system == "i686-cygwin")
+                        ./cygwin-pthread-dl.patch;
+
   doCheck = true;
 
   meta = {