https://sources.debian.org/patches/see/0.72-7/40-fix_ftbfs.patch/
https://bugs.gentoo.org/707402
--- a/src/main.h
+++ b/src/main.h
@@ -92,7 +92,8 @@ typedef struct {
 struct matchspec {
 	int bgn;
 	int end;
-} rgxp;
+};
+extern struct matchspec rgxp;
 
 /* see.c */
 void addtohistory (char *line);
--- a/src/util.c
+++ b/src/util.c
@@ -11,6 +11,7 @@ Public License along with this program.
 #include "main.h"
 
 char *EXDline, Me[64];
+struct matchspec rgxp;
 
 int buflen (char *buffer) {
 	int blen = strlen(buffer), NofL=0, i;