Re: [PATCH 2/2] [v3] kasan: use internal prototypes matching gcc-13 builtins

[Andrew Morton <akpm@linux-foundation.org>]

On Tue,  9 May 2023 16:57:21 +0200 Arnd Bergmann <arnd@kernel.org> wrote:

> gcc-13 warns about function definitions for builtin interfaces
> that have a different prototype, e.g.:
> 
> In file included from kasan_test.c:31:
> kasan.h:574:6: error: conflicting types for built-in function '__asan_register_globals'; expected 'void(void *, long int)' [-Werror=builtin-declaration-mismatch]
>   574 | void __asan_register_globals(struct kasan_global *globals, size_t size);
> kasan.h:577:6: error: conflicting types for built-in function '__asan_alloca_poison'; expected 'void(void *, long int)' [-Werror=builtin-declaration-mismatch]
>   577 | void __asan_alloca_poison(unsigned long addr, size_t size);
> kasan.h:580:6: error: conflicting types for built-in function '__asan_load1'; expected 'void(void *)' [-Werror=builtin-declaration-mismatch]
>   580 | void __asan_load1(unsigned long addr);
> kasan.h:581:6: error: conflicting types for built-in function '__asan_store1'; expected 'void(void *)' [-Werror=builtin-declaration-mismatch]
>   581 | void __asan_store1(unsigned long addr);
> kasan.h:643:6: error: conflicting types for built-in function '__hwasan_tag_memory'; expected 'void(void *, unsigned char,  long int)' [-Werror=builtin-declaration-mismatch]
>   643 | void __hwasan_tag_memory(unsigned long addr, u8 tag, unsigned long size);

I added cc:stable to these, but staged them for the next merge window.

Because I expect many people will compile earlier kernels many times
with gcc-13 and later, and they won't want to have to see these
warnings all the time.