diff --git a/ruby/Makefile.am b/ruby/Makefile.am
index 9ebcec4..8fa70b7 100644
--- a/ruby/Makefile.am
+++ b/ruby/Makefile.am
@@ -7,6 +7,7 @@ endif
 EXTRA_DIST = cucul/extconf.rb \
              cucul/cucul.c \
              cucul/cucul-canvas.c \
+             cucul/cucul-canvas.h \
              cucul/test.rb \
              cucul/t/tc_frame.rb \
              caca/extconf.rb
diff --git a/ruby/cucul/cucul-canvas.c b/ruby/cucul/cucul-canvas.c
index ad0740a..8114f68 100644
--- a/ruby/cucul/cucul-canvas.c
+++ b/ruby/cucul/cucul-canvas.c
@@ -12,6 +12,7 @@
 #include <ruby.h>
 #include <cucul.h>
 #include <errno.h>
+#include "cucul-canvas.h"
 
 #define _SELF  (DATA_PTR(self))
 
@@ -514,7 +515,7 @@ static VALUE export_memory(VALUE self, VALUE format)
     return ret;
 }
 
-static VALUE export_list()
+static VALUE export_list(void)
 {
     VALUE ary, ary2;
     
@@ -537,7 +538,7 @@ static VALUE export_list()
     return ary;
 }
 
-static VALUE import_list()
+static VALUE import_list(void)
 {
     VALUE ary, ary2;
     
diff --git a/ruby/cucul/cucul-canvas.h b/ruby/cucul/cucul-canvas.h
new file mode 100644
index 0000000..587ced3
--- /dev/null
+++ b/ruby/cucul/cucul-canvas.h
@@ -0,0 +1,6 @@
+#ifndef __CUCUL_CANVAS_H__
+#define __CUCUL_CANVAS_H__
+
+extern void Init_cucul_canvas(VALUE);
+
+#endif
diff --git a/ruby/cucul/cucul.c b/ruby/cucul/cucul.c
index b479c1a..b0222a6 100644
--- a/ruby/cucul/cucul.c
+++ b/ruby/cucul/cucul.c
@@ -12,9 +12,9 @@
 #include <ruby.h>
 #include <cucul.h>
 
-static VALUE mCucul;
+#include "cucul-canvas.h"
 
-extern void Init_cucul_canvas(VALUE);
+static VALUE mCucul;
 
 void Init_cucul()
 {