Index: Mk/Scripts/functions.sh
===================================================================
--- Mk/Scripts/functions.sh
+++ Mk/Scripts/functions.sh
@@ -153,7 +153,7 @@
 	local envfault
 	for i ; do
 		set -f
-		if ! (eval ": \${${i}?}" ) >/dev/null; then
+		if ! (eval ": \${${i}?}" ) >/dev/null 2>&1; then
 			envfault="${envfault}${envfault:+" "}${i}"
 		fi
 		set +f
@@ -165,6 +165,10 @@
 	fi
 }
 
+# Grab common environment that is expensive to lookup in downstream ports.
+# Not all of this is default known by bsd.port.mk nor is required for all
+# ports. It offers significant speedups though for anything using
+# executions (!=).
 export_ports_env() {
 	local export_vars make_cmd make_env var value uses
 
@@ -172,7 +176,7 @@
 		return 0
 	fi
 
-	validate_env MAKE PORTSDIR
+	validate_env dp_MAKE PORTSDIR
 
 	uses="python compiler:features objc"
 
@@ -186,7 +190,7 @@
 
 	make_cmd="${make_env}"
 
-	export_vars="$(${MAKE} -f ${PORTSDIR}/Mk/bsd.port.mk \
+	export_vars="$(${dp_MAKE} -f ${PORTSDIR}/Mk/bsd.port.mk \
 	    -V PORTS_ENV_VARS ${make_env} USES="${uses}")"
 
 	for var in ${export_vars}; do
@@ -194,7 +198,7 @@
 	done
 
 	# Bring in all the vars, but not empty ones.
-	eval "$(${MAKE} -f ${PORTSDIR}/Mk/bsd.port.mk ${make_cmd} \
+	eval "$(${dp_MAKE} -f ${PORTSDIR}/Mk/bsd.port.mk ${make_cmd} \
 		USES="${uses}" | grep -v '=$' | sed -e 's,\\ $,,')"
 	for var in ${export_vars}; do
 		# Export and display non-empty ones.  This is not redundant
Index: Mk/Scripts/ports_env.sh
===================================================================
--- Mk/Scripts/ports_env.sh
+++ Mk/Scripts/ports_env.sh
@@ -1,14 +1,27 @@
 #! /bin/sh
 
+#
+# Exports and gives export lines that can be evalled by the caller.
+# See export_ports_env() in functions.sh for more information.
+#
+
 # MAINTAINER: portmgr@FreeBSD.org
 
 set -o pipefail
 
-if [ -z "${SCRIPTSDIR}" ]; then
-	echo "Must set SCRIPTSDIR" >&2
+# Backwards compat for Poudriere
+if [ "${SCRIPTSDIR-__null}" != "__null" ]; then
+	dp_SCRIPTSDIR="${SCRIPTSDIR}"
+fi
+if [ "${MAKE-__null}" != "__null" ]; then
+	dp_MAKE="${MAKE}"
+fi
+
+if [ -z "${dp_SCRIPTSDIR}" ]; then
+	echo "Must set dp_SCRIPTSDIR" >&2
 	exit 1
 fi
 
-. ${SCRIPTSDIR}/functions.sh
+. ${dp_SCRIPTSDIR}/functions.sh
 
 export_ports_env
Index: Mk/Scripts/ports_env_exec.sh
===================================================================
--- /dev/null
+++ Mk/Scripts/ports_env_exec.sh
@@ -0,0 +1,18 @@
+#! /bin/sh
+
+#
+# Wrap the given command with ports_env.sh exported vars
+#
+
+# MAINTAINER: portmgr@FreeBSD.org
+
+set -o pipefail
+
+if [ -z "${dp_SCRIPTSDIR}" ]; then
+	echo "Must set dp_SCRIPTSDIR" >&2
+	exit 1
+fi
+
+. ${dp_SCRIPTSDIR}/ports_env.sh > /dev/null
+
+"$@"
Index: Mk/bsd.port.mk
===================================================================
--- Mk/bsd.port.mk
+++ Mk/bsd.port.mk
@@ -4762,7 +4762,14 @@
 .endif
 .endfor
 .endif
+# See export_ports_env() in Scripts/functions.sh
 PORTS_ENV_VARS+=	${_EXPORTED_VARS}
+PORTS_ENV_EXEC= \
+	${SETENV} \
+			PORTSDIR="${PORTSDIR}" \
+			dp_MAKE="${MAKE}" \
+			dp_SCRIPTSDIR="${SCRIPTSDIR}" \
+			${SH} ${SCRIPTSDIR}/ports_env_exec.sh
 
 .if !target(pre-check-config)
 pre-check-config: