diff -ur a/Makefile b/Makefile
--- a/Makefile	2003-08-08 00:40:39.000000000 +0900
+++ b/Makefile	2018-04-05 22:29:39.284191020 +0900
@@ -142,6 +142,7 @@
 	strip ${CS_PROGNAME}
 	strip ${BFM_PROGNAME}
 
+.PHONY: install
 install:
 	if test -x ./apg; then \
 ./mkinstalldirs ${INSTALL_PREFIX}${APG_BIN_DIR}; \