--- Makefile.in.orig	2015-05-19 13:38:35 UTC
+++ Makefile.in
@@ -1178,7 +1178,7 @@ install-exec-hook:
 	(cd $(DESTDIR)$(bindir); \
 	name=`echo gawk | sed '$(transform)'` ; \
 	$(LN) $${name}$(EXEEXT) gawk-$(VERSION)$(EXEEXT) 2>/dev/null ; \
-	if [ ! -f awk$(EXEEXT) ]; \
+	if ! /usr/bin/which -s awk; \
 	then	$(LN_S) $${name}$(EXEEXT) awk$(EXEEXT); \
 	fi; exit 0)