Index: Mk/bsd.port.mk
===================================================================
--- Mk/bsd.port.mk
+++ Mk/bsd.port.mk
@@ -1982,6 +1982,11 @@
 CHECKSUM_ALGORITHMS?= sha256
 
 DISTINFO_FILE?=		${MASTERDIR}/distinfo
+TIMESTAMP=			1461268100
+
+.if exists(${DISTINFO_FILE})
+TIMESTAMP!= ${AWK} -F' = ' -v ts=${TIMESTAMP} '/^TIMESTAMP/ { ts=$$2 } END { print ts}' ${DISTINFO_FILE}
+.endif
 
 MAKE_FLAGS?=	-f
 MAKEFILE?=		Makefile
@@ -1993,7 +1998,9 @@
 			CPP="${CPP}" CPPFLAGS="${CPPFLAGS}" \
 			LDFLAGS="${LDFLAGS}" LIBS="${LIBS}" \
 			CXX="${CXX}" CXXFLAGS="${CXXFLAGS}" \
-			MANPREFIX="${MANPREFIX}"
+			MANPREFIX="${MANPREFIX}" \
+			SOURCE_DATE_EPOCH=${TIMESTAMP}
+PKG_ENV+=	SOURCE_DATE_EPOCH=${TIMESTAMP}
 
 # Add -fno-strict-aliasing to CFLAGS with optimization level -O2 or higher.
 # gcc 4.x enable strict aliasing optimization with -O2 which is known to break