Warn about missing prototypes.

This switch warns about missing prototypes. It does not warn if
functions are declared static. So this switch encourages the usage of
static whenever possible. This enables the compiler to perform inlining.

Makefile

@@ -20,14 +20,14 @@ INSTALL_LIBRARY_PATH = $(DESTDIR)$(PREFIX)/$(LIBRARY_PATH)
 
 INSTALL ?= cp -a
 
-R_CFLAGS = -fPIC -std=c89 -pedantic -Wall -Werror -Wstrict-prototypes -Wwrite-strings -Wshadow -Winit-self -Wcast-align -Wformat=2 $(CFLAGS)
+R_CFLAGS = -fPIC -std=c89 -pedantic -Wall -Werror -Wstrict-prototypes -Wwrite-strings -Wshadow -Winit-self -Wcast-align -Wformat=2 -Wmissing-prototypes $(CFLAGS)
 
 uname := $(shell sh -c 'uname -s 2>/dev/null || echo false')
 
 #library file extensions
 SHARED = so
 STATIC = a
-
+ 
 ## create dynamic (shared) library on Darwin (base OS for MacOSX and IOS)
 ifeq (Darwin, $(uname))
 	SHARED = dylib