From 884aba608630ed772fc178542bea633de16e0f09 Mon Sep 17 00:00:00 2001
From: Albrecht Schlosser <albrechts.fltk@online.de>
Date: Mon, 14 Feb 2011 18:11:15 +0000
Subject: [PATCH] Fix threads configuration on Windows (Cygwin/MinGW), so that
 we don't try to find libpthread, unless we use Cygwin with the Cygwin dll,
 since Windows always uses native threads.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3@8422 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
---
 configure.in | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/configure.in b/configure.in
index ea84f0cfd..0d5f59b31 100644
--- a/configure.in
+++ b/configure.in
@@ -754,7 +754,24 @@ dnl Check for pthreads for multi-threaded apps...
 have_pthread=no
 PTHREAD_FLAGS=""
 
-if test "x$enable_threads" != xno; then
+dnl Test whether we want to check for pthreads. We must not do it on Windows
+dnl unless we run under Cygwin with --enable-cygwin, since we always use
+dnl native threads on Windows (even if libpthread is available)
+check_pthread=yes
+case $uname in
+    MINGW*)
+	check_pthread=no
+	;;
+    CYGWIN*)
+	if test "x$enable_cygwin" != xyes; then
+	    check_pthread=no
+	fi
+	;;
+    *)
+	;;
+esac
+
+if test "x$enable_threads" != xno -a x$check_pthread = xyes; then
     AC_CHECK_HEADER(pthread.h, AC_DEFINE(HAVE_PTHREAD_H))
 
     if test x$ac_cv_header_pthread_h = xyes; then
@@ -831,10 +848,10 @@ case $uname_GUI in
 	    if test x$have_pthread = xyes; then
 		AC_DEFINE(HAVE_PTHREAD)
 	    fi
-
-	    THREADS="threads$EXEEXT"
         fi
 
+	THREADS="threads$EXEEXT"
+
 	# Don't make symlinks since Windows is not case sensitive.
 	if test "x$with_links" != xyes; then
 		HLINKS="#"