Merge pull request #21474 from jfrazelle/fastness-for-the-storage-driver-gods

set the default storage driver as the users current default

Makefile

@@ -1,5 +1,8 @@
 .PHONY: all binary build cross default docs docs-build docs-shell shell test test-docker-py test-integration-cli test-unit validate
 
+# set the graph driver as the current graphdriver if not set
+DOCKER_GRAPHDRIVER := $(if $(DOCKER_GRAPHDRIVER),$(DOCKER_GRAPHDRIVER),$(shell docker info | grep "Storage Driver" | sed 's/.*: //'))
+
 # get OS/Arch of docker engine
 DOCKER_OSARCH := $(shell bash -c 'source hack/make/.detect-daemon-osarch && echo $${DOCKER_ENGINE_OSARCH:-$$DOCKER_CLIENT_OSARCH}')
 DOCKERFILE := $(shell bash -c 'source hack/make/.detect-daemon-osarch && echo $${DOCKERFILE}')
@@ -15,7 +18,7 @@ DOCKER_ENVS := \
 	-e DOCKER_CLIENTONLY \
 	-e DOCKER_DEBUG \
 	-e DOCKER_EXPERIMENTAL \
-	-e DOCKER_GRAPHDRIVER \
+	-e DOCKER_GRAPHDRIVER=$(DOCKER_GRAPHDRIVER) \
 	-e DOCKER_INCREMENTAL_BINARY \
 	-e DOCKER_REMAP_ROOT \
 	-e DOCKER_STORAGE_OPTS \