$OpenBSD: patch-src_gpspoint_c,v 1.3 2019/07/24 06:51:40 kirby Exp $
taken from pkgsrc/geography/viking/patch-aa
http://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=40695
Index: src/gpspoint.c
--- src/gpspoint.c.orig
+++ src/gpspoint.c
@@ -94,8 +94,8 @@ static gdouble line_altitude = VIK_DEFAULT_ALTITUDE;
 static gboolean line_visible = TRUE;
 
 static gboolean line_extended = FALSE;
-static gdouble line_speed = NAN;
-static gdouble line_course = NAN;
+static gdouble line_speed = __builtin_nanf("");
+static gdouble line_course = __builtin_nanf("");
 static gint line_sat = 0;
 static gint line_fix = 0;
 static gdouble line_hdop = VIK_DEFAULT_DOP;
