win avr gcc - nonconstant expression for length

Question

Have been tring to build this bootloader for a few days now.

https://github.com/ahtn/kp_boot_32u4

Windows pc, under mingG, WINavr and Python installed.

Im stuck at creating the elf file...

Linking: build/default-atmega32u4/kp_boot_32u4-1024-default-atmega32u4.elf
avr-gcc -mmcu=atmega32u4 -I. -Isrc -Wno-error=unused-function -DBOOT_SIZE=BOOT_SIZE_10 -DCHIP_ID=CHIP_ID_ATmega32U4 -g -DUSB_VID=0x1209 -DUSB_PID=0xBB05 -DF_CPU=16000000UL -DF_USB=UL -DBOARD=BOARD_default -DARCH=ARCH_AVR8 -D ____ -Os -fno-strict-aliasing -Wstrict-prototypes -Wa,-adhlns=build/default-atmega32u4/kp_boot_32u4-1024-default-atmega32u4.elf  -std=gnu99  -Wall -Werror -MMD -MP -MF build/default-atmega32u4/obj/.dep/kp_boot_32u4-1024-default-atmega32u4.elf.d build/default-atmega32u4/obj/usb/device_descriptors.o build/default-atmega32u4/obj/main.o build/default-atmega32u4/obj/usb.o build/default-atmega32u4/obj/spm.o --output build/default-atmega32u4/kp_boot_32u4-1024-default-atmega32u4.elf -T ./ld_scripts/avr5.xn -Wl,--section-start=.text=0x7c00 -Wl,--section-start=.boot_extra=0x7ff0 -Wl,--undefined=.boot_extra -Wl,-Map=build/default-atmega32u4/kp_boot_32u4-1024-default-atmega32u4.map,--cref -Wl,--gc-sections -flto
./ld_scripts/avr5.xn:18: nonconstant expression for length
make: *** [avr-makefile/avr.mk:253: build/default-atmega32u4/kp_boot_32u4-1024-default-atmega32u4.elf] Error 1

I uploaded a palou elf to the build folder and the make process completes ok. After a bit of research i have seen many others get the error, but wondering if there is another version of avr-gcc i could use?? to be honest i am quite new to all this so may have bitten off more than i can chew (lock down mind activity)

......

**__DATA_REGION_LENGTH__ = DEFINED(__DATA_REGION_LENGTH__) ? __DATA_REGION_LENGTH__ : 0xffa0;**

.....

and causes error in memory section...

MEMORY
{
  text   (rx)   : ORIGIN = 0, LENGTH = __TEXT_REGION_LENGTH__
  data   (rw!x) : ORIGIN = 0x800060, LENGTH = __DATA_REGION_LENGTH__

Thanks M

Answer 1

same problem here, but my mistake was putting in the wrong vales for boot section, because I could not use python. SPM_CALL_POS = 0x8000 BOOT_SECTION_START = 0x7c00 made it work.

Answer 2

These ** in avr5.xn is no valid linker script syntax. Fix that.