From 35258bf1fbf54cd0405755be0bf5a7e422a58fc1 Mon Sep 17 00:00:00 2001
From: axel <axel@liljencrantz.se>
Date: Tue, 3 Feb 2009 09:20:49 +1000
Subject: [PATCH] Make proper autoconf test for availability of posix nan
 function instead of fudging with the NAN macro.

darcs-hash:20090202232049-ac50b-0176955677ff39fdd05eeefa20dca883863c34e6.gz
---
 common.c     | 2 +-
 configure.ac | 1 +
 fallback.c   | 9 ++++++++-
 fallback.h   | 5 +++--
 4 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/common.c b/common.c
index 4a21dbb71..193783c63 100644
--- a/common.c
+++ b/common.c
@@ -1815,7 +1815,7 @@ double timef()
 	
 	if( time_res ) 
 	{
-		return NAN;
+		return nan(0);
 	}
 	
 	return (double)tv.tv_sec + 0.000001*tv.tv_usec;
diff --git a/configure.ac b/configure.ac
index cbdac650f..8c54717d4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -505,6 +505,7 @@ LIBS=""
 AC_SEARCH_LIBS( connect, socket, , [AC_MSG_ERROR([Cannot find the socket library, needed to build this package.] )] )
 AC_SEARCH_LIBS( nanosleep, rt, , [AC_MSG_ERROR([Cannot find the rt library, needed to build this package.] )] )
 AC_SEARCH_LIBS( setupterm, [ncurses curses], , [AC_MSG_ERROR([Could not find a curses implementation, needed to build fish])] )
+AC_SEARCH_LIBS( [nan], [m], [AC_DEFINE( [HAVE_NAN], [1], [Define to 1 if you have the nan function])] )
 LIBS_SHARED=$LIBS
 LIBS=$LIBS_COMMON
 
diff --git a/fallback.c b/fallback.c
index af719cf51..004e198fe 100644
--- a/fallback.c
+++ b/fallback.c
@@ -1183,5 +1183,12 @@ long sysconf(int name)
 	return -1;
 	
 }
-
 #endif
+
+#ifndef HAVE_NAN
+double nan(char *tagp)
+{
+	return 0.0/0.0;
+}
+#endif
+
diff --git a/fallback.h b/fallback.h
index 68bbcff44..e4813fb2f 100644
--- a/fallback.h
+++ b/fallback.h
@@ -469,8 +469,9 @@ long sysconf(int name);
 
 #endif
 
-#ifndef NAN
-#define NAN (0.0/0.0)
+#ifndef HAVE_NAN
+double nan(char *tagp);
 #endif
 
+
 #endif