Dear GCC hackers, I get the following output while compiling my code (isolated snippet follows): spl_mem_init.c: In function 'data_abort_memdetect_handler': spl_mem_init.c:180:1: warning: -fstack-usage not supported for this target [enabled by default] Culprit: void data_abort_memdetect_handler(void) __attribute__((naked)); void data_abort_memdetect_handler(void) { asm volatile("subs pc, r14, #4"); } gcc --version arm-linux-gnueabi-gcc (Debian 4.6.2-14) 4.6.2 Copyright (C) 2011 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Though this is observed also with stock GCC 4.6. Is there any way to tell the compiler how much stack does a naked function consume (or that it consumes zero stack)? Is this a GCC bug? Thanks in advance!
> Is there any way to tell the compiler how much stack does a naked function > consume (or that it consumes zero stack)? Is this a GCC bug? It's a limitation. We could indeed do better, but if you know how much stack space the function uses, what's the point in asking the compiler? :-)
(In reply to comment #1) > > Is there any way to tell the compiler how much stack does a naked function > > consume (or that it consumes zero stack)? Is this a GCC bug? > > It's a limitation. We could indeed do better, but if you know how much stack > space the function uses, what's the point in asking the compiler? :-) Ok, that's understandable and it's a really good function. It'd be certainly favorable to avoid using such feature (specify how much the function uses), but exactly for cases like this, it'd be very helpful to have. I'm no GC hacker myself so I have no idea how much work it'd be to write such a thing and if it'd be acceptable at all. Thanks for your quick reply!