buildroot/package/util-linux/0002-build-sys-improve-detection-of-the-isnan-function-in.patch

From 064a0445f33a67e5498d492dabe0dfc687859756 Mon Sep 17 00:00:00 2001
From: Carlos Santos <casantos@datacom.ind.br>
Date: Wed, 8 Feb 2017 09:29:30 -0200
Subject: [PATCH] build-sys: improve detection of the "isnan" function in
 uClibc

Since commit beceb14b450ded6560ed743634a5e80604a8edf3, MATH_LIBS is set
to "-lm" when the isnan function is detected. In uClibc, however, isnan
is a macro that calls __isnan, __isnanf, or __isnanl, depending on the
size of the argument (double, float or long double).

Fixes:
  http://autobuild.buildroot.net/results/2c2/2c29a78ed81ca844a87dcd076ab3e14ea080296d/
  http://autobuild.buildroot.net/results/404/404b10f359b2ae8a7216729fa1bab37fed2d3d4c/

Signed-off-by: Carlos Santos <casantos@datacom.ind.br>
---
 configure.ac | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index cc0563b..d03469c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -428,7 +428,8 @@ AC_CHECK_FUNCS([reboot], [have_reboot=yes],[have_reboot=no])
 AM_CONDITIONAL([HAVE_OPENAT], [test "x$have_openat" = xyes])
 
 AC_CHECK_FUNCS([isnan], [],
-       [AC_CHECK_LIB([m], [isnan], [MATH_LIBS="-lm"])]
+	[AC_CHECK_LIB([m], [isnan], [MATH_LIBS="-lm"])]
+	[AC_CHECK_LIB([m], [__isnan], [MATH_LIBS="-lm"])]
 )
 AC_SUBST([MATH_LIBS])
 
-- 
2.7.4