diff --git a/lib/libthr/Makefile b/lib/libthr/Makefile
index 5b3e3bff71b..fc38064cb6d 100644
--- a/lib/libthr/Makefile
+++ b/lib/libthr/Makefile
@@ -17,6 +17,7 @@ MK_SSP=	no
 LIB=thr
 SHLIB_MAJOR= 3
 WARNS?=	3
+NO_WTHREAD_SAFETY=1
 CFLAGS+=-DPTHREAD_KERNEL
 CFLAGS+=-I${SRCTOP}/lib/libc/include -I${.CURDIR}/thread \
 	-I${SRCTOP}/include