--- src/VBox/Runtime/Makefile.kmk.orig	2021-01-07 15:41:50 UTC
+++ src/VBox/Runtime/Makefile.kmk
@@ -177,6 +177,11 @@ $(IPRT_OUT_DIR)/oiddb.h.ts +| $(IPRT_OUT_DIR)/oiddb.h:
 
 
 #
+# Set the defines that utf8-posix.cpp needs. It's used by several targets.
+#
+r3/posix/utf8-posix.cpp_DEFS.freebsd = $(VBOX_ICONV_DEFS)
+
+#
 # Unicode Specification reader used to regenerate unidata-*.cpp.
 #
 uniread_TEMPLATE = VBoxBldProg