--- libr/util/Makefile.orig	2021-02-13 20:27:05 UTC
+++ libr/util/Makefile
@@ -52,7 +52,7 @@ endif
 endif
 
 # FreeBSD 10.0 ships with backtrace(3) in -lexecinfo
-ifeq (${BUILD_OS},freebsd)
+ifeq (${HOST_OS},freebsd)
 ifneq ($(shell expr "`uname -r`" : '[0-9]\.'), 2)
   LDFLAGS+=-lexecinfo
 endif