Compile with -rdynamic on UNIXCOMMON platforms

src/sdl/MakeNIX.cfg

@@ -18,9 +18,11 @@ endif
 #
 #here is GNU/Linux and other
 #
-
 	OPTS=-DUNIXCOMMON
 
+#Use -rdynamic so a backtrace log shows function names instead of addresses
+	LDFLAGS+=-rdynamic
+
 	#LDFLAGS = -L/usr/local/lib
 	LIBS=-lm
 ifdef LINUX