I'm using armclang compiler Product: Professional Component: ARM Compiler 6.16
There are unused functions which are linked in the final application. There functions are coming from a library which is linked to final application, but not called in application.
How to remove these unused functions from final image ?
I am referring to an ELF (the format of Arm objects and images) section.
By removing --no_remove from linker, the function
void __stack_chk_fail(void) got removed.
This function is called by compiler upon stack overflow check, so there is no call in the application explicitly.
How to prevent these functions getting removed, also exceptions, interrupt service routines won't have any callgrah.
Use --keep <object containing this function> on the linker command line.
This seems to be tedious, for example if a file foo.o contains functions which are called and some are unused. Specifying each, of these to keep is cumbersome. Is there a better way to remove the unused functions while keeping the ones which are required like compiler calling functions like __stack_chck_fail().
Also after using --keep=foo_*.o it is showing so many 8 bytes removed, though they are being called from caller functions. .ARM.exidx.text.foo_test ), (8 bytes). What is this .exidx sections ?
Is it removing the functions or some data, it seems only 8 bytes.
Removing foo_test.o(.ARM.exidx.text.foo_test_init), (8 bytes).Removing foo_test.o(.ARM.exidx.text.foo_test_getHandle), (8 bytes).Removing foo_test.o(.ARM.exidx.text.foo_test_setType0), (8 bytes).Removing foo_test.o(.ARM.exidx.text.foo_test_SetupType0In), (8 bytes).Removing foo_test.o(.ARM.exidx.text.foo_test_cfgPort), (8 bytes).Removing foo_test.o(.ARM.exidx.text.foo_test_StatusCmd), (8 bytes).Removing foo_test.o(.ARM.exidx.text.foo_test_cfgTimerCtrl), (8 bytes).Removing foo_test.o(.ARM.exidx.text.foo_test_SetLm), (8 bytes).Removing foo_test.o(.ARM.exidx.text.foo_test_cfgP0Ctrl), (8 bytes).
I am not aware of another solution.