-LIBGCC_S=$(if $(wildcard $(TOOLCHAIN_DIR)/lib/libgcc_s.so),-L$(TOOLCHAIN_DIR)/lib -lgcc_s,$(wildcard $(TOOLCHAIN_DIR)/lib/gcc/*/*/libgcc.a))
+ifneq ($(CONFIG_EXTERNAL_TOOLCHAIN),)
+LIBGCC_S_PATH=$(realpath $(wildcard $(call qstrip,$(CONFIG_LIBGCC_ROOT_DIR))/$(call qstrip,$(CONFIG_LIBGCC_FILE_SPEC))))
+LIBGCC_S=$(if $(LIBGCC_S_PATH),-L$(dir $(LIBGCC_S_PATH)) -lgcc_s)
+LIBGCC_A=$(realpath $(lastword $(wildcard $(dir $(LIBGCC_S_PATH))/gcc/*/*/libgcc.a)))
+else
+LIBGCC_A=$(lastword $(wildcard $(TOOLCHAIN_DIR)/lib/gcc/*/*/libgcc.a))
+LIBGCC_S=$(if $(wildcard $(TOOLCHAIN_DIR)/lib/libgcc_s.so),-L$(TOOLCHAIN_DIR)/lib -lgcc_s,$(LIBGCC_A))
+endif
+LIBRPC=-lrpc
+LIBRPC_DEPENDS=+librpc
+
+ifeq ($(CONFIG_ARCH_64BIT),y)
+ LIB_SUFFIX:=64
+endif