Change Makefile to not delete legacy binaries, but instead just notify the user about them. Change Makefile to only look for legacy binaries in $PREFIX instead of using which.

https://github.com/fish-shell/fish-shell/pull/655

Makefile.in

@@ -509,23 +509,20 @@ check-uninstall:
 	fi;
 .PHONY: check-uninstall
 
-
-# seq used to be a shell script that we would install
-# Now we just look for previously installed seqs, and erase them
-# No big deal if it fails
-# same with set_color, which is now a builtin.
-# Invoke set_color with -v to make sure it's ours.
-cleanup_old_binaries:
-	SEQLOC=`which seq`;\
-	if test -x "$$SEQLOC" && grep -q '\(^#!/.*/fish\|^#!/usr/bin/env fish\)' "$$SEQLOC"; then\
-		rm -f "$$SEQLOC";\
-	fi;\
-	SETCOLOR_LOC=`which set_color`;\
+check-legacy-binaries:
+	@SEQLOC=$(prefix)/bin/seq;\
+	if test -f "$$SEQLOC" && grep -q '\(^#!/.*/fish\|^#!/usr/bin/env fish\)' "$$SEQLOC"; then\
+		echo "An outdated seq from a previous fish install was found. You should remove it with:";\
+		echo "    rm '$$SEQLOC'";\
+	fi;
+	@SETCOLOR_LOC=$(prefix)/bin/set_color;\
 	if test -x "$$SETCOLOR_LOC" && $$SETCOLOR_LOC -v 2>&1 >/dev/null | grep -q "^set_color, version "; then\
-		rm -f "$$SETCOLOR_LOC";\
-	fi;\
-	true;
-.PHONY: cleanup_old_binaries
+		echo "An outdated set_color from a previous fish install was found. You should remove it with:";\
+		echo "    rm '$$SETCOLOR_LOC'";\
+	fi;
+	@true;
+.PHONY: check-legacy-binaries
+
 
 #
 # This check makes sure that the install-sh script is executable. The
@@ -542,7 +539,7 @@ install-sh:
 # Try to install after checking for incompatible installed versions.
 #
 
-install: all cleanup_old_binaries install-sh check-uninstall install-force
+install: all install-sh check-uninstall install-force check-legacy-binaries
 .PHONY: install
 
 #