--- Makefile.orig	2022-02-23 04:42:33 UTC
+++ Makefile
@@ -23,6 +23,8 @@ pcalc: LDFLAGS += $(CFLAGS)
 pcalc: $(OBJS)
 pcalc: LDFLAGS += $(CFLAGS)
 
+$(OBJS): pcalc.c
+
 pcalc.c: pcalc.y
 	$(YACC) -o $@ $<
 
@@ -39,10 +41,10 @@ INSTALL = install
 	$(MAKE) -C ptest check
 
 INSTALL = install
-BINDIR  = /usr/bin
+BINDIR  = $(PREFIX)/bin
 DESTDIR = 
 install:
-	$(INSTALL) -m 755 -D pcalc $(DESTDIR)$(BINDIR)/pcalc
+	$(BSD_INSTALL_PROGRAM) pcalc $(DESTDIR)$(BINDIR)/pcalc
 
 dist pack: distclean
 	rm -rf pcalc-$(VERSION)