1 files changed, 77 insertions, 0 deletions
diff --git a/examples/build_system/make/toolchain/gcc_rules.mk b/examples/build_system/make/toolchain/gcc_rules.mk
new file mode 100644
index 000000000..fc5225503
--- /dev/null
+++ b/examples/build_system/make/toolchain/gcc_rules.mk
@@ -0,0 +1,77 @@
+SRC_S += $(SRC_S_GCC)
+
+# Assembly files can be name with upper case .S, convert it to .s
+SRC_S := $(SRC_S:.S=.s)
+
+# Due to GCC LTO bug https://bugs.launchpad.net/gcc-arm-embedded/+bug/1747966
+# assembly file should be placed first in linking order
+# '_asm' suffix is added to object of assembly file
+OBJ += $(addprefix $(BUILD)/obj/, $(SRC_S:.s=_asm.o))
+OBJ += $(addprefix $(BUILD)/obj/, $(SRC_C:.c=.o))
+
+CFLAGS += $(CFLAGS_GCC) -MD
+
+# LTO makes it difficult to analyze map file for optimizing size purpose
+# We will run this option in ci
+ifeq ($(NO_LTO),1)
+CFLAGS := $(filter-out -flto,$(CFLAGS))
+endif
+
+ifneq ($(CFLAGS_SKIP),)
+CFLAGS := $(filter-out $(CFLAGS_SKIP),$(CFLAGS))
+endif
+
+ifeq ($(TOOLCHAIN),clang)
+CFLAGS += $(CFLAGS_CLANG)
+LDFLAGS += $(CFLAGS) $(LDFLAGS_CLANG)
+else
+LDFLAGS += $(CFLAGS) $(LDFLAGS_GCC)
+endif
+
+# TODO should be removed after all examples are updated
+ifdef LD_FILE
+LDFLAGS += -Wl,-T,$(TOP)/$(LD_FILE)
+endif
+
+ifdef LD_FILE_GCC
+LDFLAGS += -Wl,-T,$(TOP)/$(LD_FILE_GCC)
+endif
+
+ASFLAGS += $(CFLAGS)
+
+# libc
+ifneq ($(BOARD), spresense)
+LIBS += -lc
+endif
+
+# ---------------------------------------
+# Rules
+# ---------------------------------------
+
+# Compile .c file
+$(BUILD)/obj/%.o: %.c
+	@echo CC $(notdir $@)
+	@$(CC) $(CFLAGS) -c -o $@ $<
+
+# ASM sources lower case .s
+$(BUILD)/obj/%_asm.o: %.s
+	@echo AS $(notdir $@)
+	@$(AS) $(ASFLAGS) -c -o $@ $<
+
+# ASM sources upper case .S
+$(BUILD)/obj/%_asm.o: %.S
+	@echo AS $(notdir $@)
+	@$(AS) $(ASFLAGS) -c -o $@ $<
+
+OBJCOPY_BIN_OPTION ?=
+$(BUILD)/$(PROJECT).bin: $(BUILD)/$(PROJECT).elf
+	@echo CREATE $@
+	$(OBJCOPY) -O binary $(OBJCOPY_BIN_OPTION) $^ $@
+
+$(BUILD)/$(PROJECT).hex: $(BUILD)/$(PROJECT).elf
+	@echo CREATE $@
+	@$(OBJCOPY) -O ihex $^ $@
+
+$(BUILD)/$(PROJECT).elf: $(OBJ)
+	@echo LINK $@
+	@$(LD) -o $@ $(LDFLAGS) $^ -Wl,--start-group $(LIBS) -Wl,--end-group