Using $< in a non-suffix rule context is a GNUmake idiom.

Using the "define" directive is a GNUmake idiom.

Index: Makefile.in
--- Makefile.in.orig
+++ Makefile.in
@@ -1303,11 +1303,6 @@ uninstall-man: uninstall-man1
 .PRECIOUS: Makefile
 
 
-define check-exit
-|| exit 1
-
-endef
-
 # -------
 # Targets
 # -------
@@ -1342,7 +1337,7 @@ cleanall: clean distclean
 	-git clean -fxd
 
 monit.1: doc/monit.pod
-	$(POD2MAN) $(POD2MANFLAGS) $< > $@
+	$(POD2MAN) $(POD2MANFLAGS) doc/monit.pod > $@
 	-rm -f pod2*
 
 # -------------
@@ -1353,14 +1348,14 @@ src/y.tab.c src/y.tab.h: run-yacc
 
 .INTERMEDIATE: run-yacc
 run-yacc: src/p.y
-	$(YACC) $(YACCFLAGS) -o src/y.tab.c $<
+	$(YACC) $(YACCFLAGS) -o src/y.tab.c src/p.y
 
 src/lex.yy.c: src/l.l
-	$(FLEX) $(FLEXFLAGS) -o$@ $<
+	$(FLEX) $(FLEXFLAGS) -o$@ src/l.l
 @WITH_CODESIGN_TRUE@all-local: $(bin_PROGRAMS)
 @WITH_CODESIGN_TRUE@	$(foreach file, $(bin_PROGRAMS), \
 @WITH_CODESIGN_TRUE@                codesign -s $(CODESIGN_IDENTITY) -v --deep --timestamp --options runtime $(file) \
-@WITH_CODESIGN_TRUE@        $(check-exit))
+@WITH_CODESIGN_TRUE@        || exit 1)
 
 # Tell versions [3.59,3.63) of GNU make to not export all variables.
 # Otherwise a system limit (for SysV at least) may be exceeded.