- Wed Mar 27, 2019 7:39 pm
#81400
I'm starting this thread to capture the conversation thread that started on the NonOS Git repo where compiler settings were discussed.
Moderator: eriksl
- Wed Mar 27, 2019 7:41 pm
#81401
These are my current settings, which I modified based on the discussion. I know others have slightly different settings too so post them up!
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DEFINES = -D__ets__ -DICACHE_FLASH -DMEM_DEFAULT_USE_DRAM -DSPI_FLASH_SIZE_MAP=${SPI_SIZE_MAP} -DBUILD_ID="\"I${BUILD_DATE}\"" -DDEBUG_ON -DMQTT_DEBUG_ON
# compiler flags using during compilation of source files
CFLAGS = -std=gnu99 -flto -Wpointer-arith -Wundef -Werror -Wmissing-prototypes -Wstrict-prototypes -fno-builtin -fno-builtin-printf -fno-guess-branch-probability -freorder-blocks-and-partition -fno-cse-follow-jumps -ffunction-sections -fdata-sections -fno-inline-functions -nostdlib -mlongcalls -mtext-section-literals -mno-serialize-volatile ${DEFINES}
CXXFLAGS = $(CFLAGS) -fno-rtti -fno-exceptions
# linker flags used to generate the main object file
LDFLAGS = $(CFLAGS) -Wl,-EL -Wl,-flto -Wl,-gc-sections -Wl,--no-check-sections -u call_user_start -Wl,-static -Wl,--print-memory-usage -Wl,--cref -Wl,-Map=link.map #-Wl,-print-map
# linker script used for the above linker step
LD_SCRIPT = eagle.app.v6.ld
ifeq ($(ENABLE_GDB), 1)
CFLAGS += -Og -ggdb -DENABLE_GDB=1
MODULES += gdbstub
EXTRA_INCDIR += gdbstub
else
CFLAGS += -Os
endif
- Mon Apr 01, 2019 2:03 pm
#81485
Good initiative!
Do you need this one?
Regarding LTO: I've experienced most of the time IRAM usage decreases quite a bit, but:
- not always, sometime the usage even goes up
- it will mangle all symbols, if you're debugging or scanning memory usage, turn it off
- I'd recommend these flags using fto:
- no need to use
Do you need this one?
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I think it's dangerous and not required.-Wl,--no-check-sections Regarding LTO: I've experienced most of the time IRAM usage decreases quite a bit, but:
- not always, sometime the usage even goes up
- it will mangle all symbols, if you're debugging or scanning memory usage, turn it off
- I'd recommend these flags using fto:
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. -flto=x uses x threads, which may speed up linking; also you must use fat-lto-object or otherwise esptool(2) can't handle the resulting object file. Mostly -flto-partition=max gives best results (other than the default), but not always.-flto=8 -flto-compression-level=0 -fuse-linker-plugin -ffat-lto-objects -flto-partition=max- no need to use
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, the linker recognises -flto. Even more, it's required that the linker gets exactly the same flags as the compiler (in this case the linker will do part of the actual compilation, the compiler will only generate intermediate code).
-Wl,-flto
- Mon Apr 01, 2019 2:05 pm
#81486
The relevant parts of my makefile:
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WARNINGS := -Wall -Wextra -Werror \
-Wformat-overflow=2 -Wshift-overflow=2 -Wimplicit-fallthrough=5 \
-Wformat-signedness -Wformat-truncation=2 \
-Wstringop-overflow=4 -Wunused-const-variable=2 -Walloca \
-Warray-bounds=2 -Wswitch-bool -Wsizeof-array-argument \
-Wduplicated-branches -Wduplicated-cond -Wlto-type-mismatch -Wnull-dereference \
-Wdangling-else -Wno-incompatible-pointer-types \
-Wpacked -Wfloat-equal -Winit-self -Wmissing-include-dirs -Wstrict-overflow=2 \
-Wno-format -Wmissing-noreturn -Wbool-compare \
-Wsuggest-attribute=noreturn -Wsuggest-attribute=format -Wmissing-format-attribute \
-Wuninitialized -Wtrampolines -Wframe-larger-than=1024 \
-Wunsafe-loop-optimizations -Wshadow -Wpointer-arith -Wbad-function-cast \
-Wcast-qual -Wwrite-strings -Wsequence-point -Wlogical-op -Wlogical-not-parentheses \
-Wredundant-decls -Wvla -Wdisabled-optimization \
-Wunreachable-code -Wparentheses -Wdiscarded-array-qualifiers \
-Wmissing-prototypes -Wold-style-definition -Wold-style-declaration -Wmissing-declarations \
-Wcast-align -Winline \
-Wno-pointer-sign -Wno-unused-parameter -Wno-attributes \
-Wno-error=cast-qual -Wno-error=packed -Wno-error=unsafe-loop-optimizations
CFLAGS := -pipe -O3 -g -std=gnu11 -fdiagnostics-color=always \
-ffreestanding -fno-inline -mlongcalls -mno-serialize-volatile -mno-target-align \
-fno-math-errno -fno-printf-return-value \
-fno-tree-forwprop \
-ffunction-sections -fdata-sections
ifeq ($(USE_LTO),1)
CFLAGS += -flto=8 -flto-compression-level=0 -fuse-linker-plugin -ffat-lto-objects -flto-partition=max
endif
CFLAGS += -D__ets__ -DICACHE_FLASH -DLWIP_OPEN_SRC -DPBUF_RSV_FOR_WLAN -DEBUF_LWIP \
-DBOOT_BIG_FLASH=1 -DBOOT_RTC_ENABLED=1 \
-DIMAGE_TYPE=$(IMAGE) -DIMAGE_OTA=$(IMAGE_OTA) \
-DUSER_CONFIG_SECTOR=$(USER_CONFIG_SECTOR) -DUSER_CONFIG_OFFSET=$(USER_CONFIG_OFFSET) -DUSER_CONFIG_SIZE=$(USER_CONFIG_SIZE) \
-DRFCAL_OFFSET=$(RFCAL_OFFSET) -DRFCAL_SIZE=$(RFCAL_SIZE) \
-DPHYDATA_OFFSET=$(PHYDATA_OFFSET) -DPHYDATA_SIZE=$(PHYDATA_SIZE) \
-DSYSTEM_CONFIG_OFFSET=$(SYSTEM_CONFIG_OFFSET) -DSYSTEM_CONFIG_SIZE=$(SYSTEM_CONFIG_SIZE) \
-DOFFSET_OTA_IMG_0=$(OFFSET_OTA_IMG_0) -DOFFSET_OTA_IMG_1=$(OFFSET_OTA_IMG_1) -DSIZE_OTA_IMG=$(SIZE_OTA_IMG) \
-DOFFSET_IRAM_PLAIN=$(OFFSET_IRAM_PLAIN) -DSIZE_IRAM_PLAIN=$(SIZE_IRAM_PLAIN) \
-DOFFSET_IROM_PLAIN=$(OFFSET_IROM_PLAIN) -DSIZE_IROM_PLAIN=$(SIZE_IROM_PLAIN) \
-DSEQUENCER_FLASH_OFFSET=$(SEQUENCER_FLASH_OFFSET_0) -DSEQUENCER_FLASH_SIZE=$(SEQUENCER_FLASH_SIZE) \
-DSEQUENCER_FLASH_OFFSET_0=$(SEQUENCER_FLASH_OFFSET_0) -DSEQUENCER_FLASH_OFFSET_1=$(SEQUENCER_FLASH_OFFSET_1) \
-DOFFSET_OTA_BOOT=$(OFFSET_OTA_BOOT) -DSIZE_OTA_BOOT=$(SIZE_OTA_BOOT) \
-DOFFSET_OTA_RBOOT_CFG=$(OFFSET_OTA_RBOOT_CFG) -DSIZE_OTA_RBOOT_CFG=$(SIZE_OTA_RBOOT_CFG) \
-DFLASH_SIZE_SDK=$(FLASH_SIZE_SDK)
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CINC := -I$(HAL)/include \
-I$(ESPOPENSDK)/xtensa-lx106-elf/xtensa-lx106-elf/include \
-I$(LWIP)/include -I$(LWIP)/include/lwip -I .
LDFLAGS := -L. -L$(ESPSDK)/lib -Wl,--size-opt -Wl,--print-memory-usage -Wl,--gc-sections -Wl,--cref -Wl,-Map=$(LINKMAP) -nostdlib -u call_user_start -Wl,-static
SDKLIBS := -lhal -lpp -lphy -lnet80211 -lwpa
LWIPLIBS := -l$(LIBLWIPAPP) -l$(LIBLWIPCORE) -l$(LIBLWIPNETIF)
STDLIBS := -lm -lgcc -lcrypto
