1
0
mirror of https://github.com/RIOT-OS/RIOT.git synced 2025-01-18 12:52:44 +01:00
RIOT/makefiles/arch/atmega.inc.mk
Juan Carrano 63c475cd4d toolchain/cflags: enable dwarf compression.
Use the -gz option to compress ELF sections containing DWARF information.
This saves around 50% of disk space, without any side effects.

See https://gcc.gnu.org/onlinedocs/gcc-9.2.0/gcc/Debugging-Options.html#Debugging-Options
for more infomation on this option.

Some platforms have an outdated toolchain that does not support -gz so
the flag is blacklisted there. Even then, the results are quite impressive.

I used @cladmi's `buildtest` branch (https://github.com/cladmi/RIOT/tree/wip/du/buildtest)
with this change and compiled the `examples/default` application:

```
$ BUILD_IN_DOCKER=1 DOCKER="sudo docker" make -C examples/default buildtest-indocker
```

The size was obtained with:

```
$ find output -name "*.bin.bindirsize" -type f -exec tail  -n1 '{}' \; | cut -f 1 | awk '{s+=$1} END {printf "%.0f", s}'
```

Results:

- Vanilla: 10328112 KB (~10GB).
- with -gz: 4982788 KB (~5GB).

This was inspired by #8496.
2019-09-02 14:43:26 +02:00

57 lines
2.2 KiB
Makefile

# Target architecture for the build. Use avr if you are unsure.
TARGET_ARCH ?= avr
CFLAGS_CPU = -mmcu=$(CPU) $(CFLAGS_FPU)
CFLAGS_LINK = -ffunction-sections -fdata-sections -fno-builtin -fshort-enums
CFLAGS_DBG ?= -ggdb -g3
CFLAGS_OPT ?= -Os
CFLAGS += $(CFLAGS_CPU) $(CFLAGS_LINK) $(CFLAGS_DBG) $(CFLAGS_OPT)
ASFLAGS += $(CFLAGS_CPU) $(CFLAGS_DBG)
LINKFLAGS += $(CFLAGS_CPU) $(CFLAGS_DBG) $(CFLAGS_OPT) -static -lgcc -e reset_handler -Wl,--gc-sections
OFLAGS += -j .text -j .data
# Tell the build system that the CPU depends on the atmega common files:
USEMODULE += atmega_common
# export the peripheral drivers to be linked into the final binary
USEMODULE += atmega_common_periph
# Export the peripheral drivers to be linked into the final binary, for now
# only atmega126rfr2 has periph drivers
ifeq ($(CPU), atmega256rfr2)
USEMODULE += periph
endif
# the atmel port uses stdio_uart
USEMODULE += stdio_uart
# explicitly tell the linker to link the syscalls and startup code.
# without this the interrupt vectors will not be linked correctly!
UNDEF += $(BINDIR)/atmega_common/startup.o
# 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)
# Use newer linker script to have ROM/RAM configuration symbols in binutils<2.26
LDSCRIPT_COMPAT = $(if $(shell $(TARGET_ARCH)-ld --verbose | grep __TEXT_REGION_LENGTH__),,\
-T$(RIOTCPU)/$(CPU)/ldscripts_compat/avr_2.26.ld)
LINKFLAGS += $(LDSCRIPT_COMPAT)
# use the wrapper functions for following avr-libc functions
LINKFLAGS += -Wl,-wrap=malloc -Wl,-wrap=calloc -Wl,-wrap=realloc -Wl,-wrap=free
ifeq ($(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