--- hpt/Makefile.orig	2020-01-16 21:50:04 UTC
+++ hpt/Makefile
@@ -33,6 +33,7 @@ endif
 ifeq ($(PERL), 1)
   CFLAGS += -DDO_PERL `perl -MExtUtils::Embed -e ccopts`
   PERLLIBS = `perl -MExtUtils::Embed -e ldopts`
+  LFLAGS += $(PERLLIBS)
   PERLOBJ = perl$(_OBJ)
 endif
 
@@ -61,10 +62,10 @@ all: commonall hpt.1.gz hptlink.1.gz hpttree.1.gz txt2
 endif
 
 doc:
-	-cd doc; make all
+	-cd doc; $(MAKE) all
 
 install-doc:
-	-cd doc; make install
+	-cd doc; $(MAKE) install
 
 ifeq ($(SHORTNAMES), 1)
 install: hpt$(_EXE) pktinfo$(_EXE) txt2pkt$(_EXE) hptlink$(_EXE) hpttree$(_EXE)