# Target architecture for the build. Use avr if you are unsure.
TARGET_ARCH_AVR ?= avr
TARGET_ARCH ?= $(TARGET_ARCH_AVR)

ifeq (atxmega,$(CPU))
  ifeq (,$(CPU_MODEL))
    $(error CPU_MODEL must have been defined by the board Makefile.features)
  endif
  CFLAGS_CPU ?= -mmcu=$(CPU_MODEL) $(CFLAGS_FPU)
else
  CFLAGS_CPU ?= -mmcu=$(CPU) $(CFLAGS_FPU)
endif
CFLAGS_LINK  = -ffunction-sections -fdata-sections -fno-builtin -fshort-enums
CFLAGS_DBG  ?= -ggdb -g3
CFLAGS_OPT  ?= -Os

# Use of __flash requires gnu11 instead of c11
CFLAGS    += -std=gnu11

CFLAGS    += $(CFLAGS_CPU) $(CFLAGS_LINK) $(CFLAGS_DBG) $(CFLAGS_OPT)
ASFLAGS   += $(CFLAGS_CPU) $(CFLAGS_DBG)

LINKFLAGS += $(CFLAGS_CPU) $(CFLAGS_DBG) $(CFLAGS_OPT) -static -lgcc -e reset_handler -Wl,--gc-sections
LINKFLAGS += -L$(RIOTCPU)/avr8_common/ldscripts
LINKFLAGS += -T$(LINKER_SCRIPT)

# Use ROM_LEN and RAM_LEN during link
$(if $(ROM_LEN),,$(error ROM_LEN is not defined))
$(if $(RAM_LEN),,$(error RAM_LEN is not defined))
LINKFLAGS += $(LINKFLAGPREFIX)--defsym=__TEXT_REGION_LENGTH__=$(ROM_LEN)$(if $(ROM_RESERVED),-$(ROM_RESERVED))
LINKFLAGS += $(LINKFLAGPREFIX)--defsym=__DATA_REGION_LENGTH__=$(RAM_LEN)
LINKFLAGS += $(LDSCRIPT_EXTRA)

ifeq ($(LTO),1)
  # avr-gcc <4.8.3 has a bug when using LTO which causes a warning to be printed always:
  # '_vector_25' appears to be a misspelled signal handler [enabled by default]
  # See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59396
  LINKFLAGS += -Wno-error
endif

OPTIONAL_CFLAGS_BLACKLIST += -Wformat-overflow
OPTIONAL_CFLAGS_BLACKLIST += -Wformat-truncation
OPTIONAL_CFLAGS_BLACKLIST += -gz