nano-vfprintf_float.c: Fix check if negative for nans.

diff --git a/newlib/libc/stdio/nano-vfprintf_float.c b/newlib/libc/stdio/nano-vfprintf_float.c
index 071a09edc60504c6105b5c08a2c21a634d144804..524f67a31383b165245fb3e804f33995fbdbacf4 100644 (file)
--- a/newlib/libc/stdio/nano-vfprintf_float.c
+++ b/newlib/libc/stdio/nano-vfprintf_float.c
@@ -39,6 +39,7 @@
 #include <string.h>
 #include <limits.h>
 #include <stdint.h>
+#include <math.h>
 #include <wchar.h>
 #include <sys/lock.h>
 #include <stdarg.h>
@@ -213,7 +214,7 @@ _printf_float (struct _reent *data,
     }
   if (isnan (_fpvalue))
     {
-      if (_fpvalue < 0)
+      if (signbit (_fpvalue))
        pdata->l_buf[0] = '-';
       if (code <= 'G')         /* 'A', 'E', 'F', or 'G'.  */
        cp = "NAN";