diff --git a/tests/common.mk b/tests/common.mk
index ef6982514..0e85e9fb9 100644
--- a/tests/common.mk
+++ b/tests/common.mk
@@ -1,9 +1,16 @@
 ROOT_DIR := $(abspath $(dir $(lastword $(MAKEFILE_LIST))))
 BUILD_DIR ?= $(ROOT_DIR)/..
+ifneq ($(wildcard $(ROOT_DIR)/../Makefile.conf),)
+include $(ROOT_DIR)/../Makefile.conf
+endif
 
 SBY   ?= sby
 YOSYS ?= $(BUILD_DIR)/yosys
+ifneq ($(ABCEXTERNAL),)
+ABC	  ?= $(ABCEXTERNAL)
+else
 ABC   ?= $(BUILD_DIR)/yosys-abc
+endif
 YOSYS_FILTERLIB ?= $(BUILD_DIR)/yosys-filterlib
 YOSYS_CONFIG ?= $(BUILD_DIR)/yosys-config
 YOSYS_SMTBMC ?= $(BUILD_DIR)/yosys-smtbmc