--- C/Makefile.orig	2019-10-30 18:14:13 UTC
+++ C/Makefile
@@ -29,7 +29,7 @@ TEST = test
 ###
 # installation options
 #
-prefix = /usr/local
+prefix ?= /usr/local
 LOCALEDIR = $(prefix)/share/locale
 
 ###
@@ -178,7 +178,7 @@ bsd43-cc:
 	$(MAKE) _MKCONFIG_SHELL=$(MKCONFIG_SHELL) \
 		CC=cc LD=cc EXE_EXT="" OBJ_EXT=".o" \
 		DI_CFLAGS="$(DI_CFLAGS) -O" \
-		LDFLAGS="-O" di-programs
+		LDFLAGS="-O $(LDFLAGS)" di-programs
 
 .PHONY: bsd43-gcc
 bsd43-gcc:
@@ -192,7 +192,7 @@ bsd43-gcc:
 	$(MAKE) _MKCONFIG_SHELL=$(MKCONFIG_SHELL) \
 		CC=gcc LD=gcc EXE_EXT="" OBJ_EXT=".o" \
 		DI_CFLAGS="$(DI_CFLAGS) -O2" \
-		LDFLAGS="-O2" di-programs
+		LDFLAGS="-O2 $(LDFLAGS)" di-programs
 
 .PHONY: ultrix-cc
 ultrix-cc: