We should use extern variable due gcc10 update

Makefile

+PACKAGENAME = 'cdrkit-1.1.11'
+
 all:
-	tar xf cdrkit-1.1.11.tar.gz
-	$(MAKE) -C cdrkit-1.1.11
-	$(MAKE) -C cdrkit-1.1.11 install PREFIX=/usr
-	rm -rf cdrkit-1.1.11
+	tar xf $(PACKAGENAME).tar.gz
+	patch -Np1 -d $(PACKAGENAME) < $(PACKAGENAME)-gcc10.patch
+	$(MAKE) -C $(PACKAGENAME)
+	$(MAKE) -C $(PACKAGENAME) install PREFIX=/usr
\ No newline at end of file
+	rm -rf $(PACKAGENAME)

cdrkit-1.1.11-gcc10.patch

+diff -Naur cdrkit-1.1.11/genisoimage/genisoimage.h cdrkit-1.1.11.patched/genisoimage/genisoimage.h
+--- cdrkit-1.1.11/genisoimage/genisoimage.h	2008-05-26 06:00:55.000000000 +0900
++++ cdrkit-1.1.11.patched/genisoimage/genisoimage.h	2021-09-08 09:46:54.865911289 +0800
+@@ -376,7 +376,7 @@
+ extern int	split_SL_component;
+ extern int	split_SL_field;
+ extern char	*trans_tbl;
+-char		*outfile;
++extern char	*outfile;
+ 
+ #define	JMAX		64	/* maximum Joliet file name length (spec) */
+ #define	JLONGMAX	103	/* out of spec Joliet file name length */