"Tzu-Chien Chiu" <tzuchien.chiu@gmail.com> writes: > I got a warning from ld: "gc-sections option ignored." That means that your specific backend does not have support for gc-sections. > or32-elf-gcc -o a.o -c -ffunction-sections -fdata-sections a.c You need to add gc_mark_hook and gc_sweep_hook functions to bfd/elf32-or32.c. Ian