--- groff-1.18.1.1/src/preproc/grn/hgraph.cc.orig	2002-10-07 13:49:03.000000000 +0900
+++ groff-1.18.1.1/src/preproc/grn/hgraph.cc	2016-01-01 10:15:57.000000000 +0900
@@ -43,7 +43,7 @@
 extern int ybottom;
 extern int xleft;
 extern int xright;
-extern enum {
+extern enum filtype {
   OUTLINE, FILL, BOTH
 } polyfill;
 
--- groff-1.18.1.1/src/preproc/grn/main.cc.orig	2002-02-10 10:22:12.000000000 +0900
+++ groff-1.18.1.1/src/preproc/grn/main.cc	2016-01-01 10:17:52.000000000 +0900
@@ -160,7 +160,7 @@
 double scale = 1.0;		/* no scaling, default */
 int defpoint = 0;		/* flag for pointsize scaling */
 char *defstipple = (char *) 0;
-enum {
+enum filltype {
   OUTLINE, FILL, BOTH
 } polyfill;