Re: linux-next: build warning after merge of the tip tree

Ard Biesheuvel
2020-12-14T07:33:26Z

On Mon, 14 Dec 2020 at 06:48, Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> Hi all,
>
> After merging the tip tree, today's linux-next build (arm
> multi_v7_defconfig) produced this warning:
>
> In file included from include/linux/kernel.h:14,
> from include/linux/list.h:9,
> from include/linux/wait.h:7,
> from include/linux/wait_bit.h:8,
> from include/linux/fs.h:6,
> from include/linux/proc_fs.h:10,
> from include/linux/efi.h:19,
> from drivers/firmware/efi/libstub/arm32-stub.c:5:
> drivers/firmware/efi/libstub/arm32-stub.c: In function 'handle_kernel_image':
> include/linux/minmax.h:18:28: warning: comparison of distinct pointer types lacks a cast
> 18 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
> | ^~
> include/linux/minmax.h:32:4: note: in expansion of macro '__typecheck'
> 32 | (__typecheck(x, y) && __no_side_effects(x, y))
> | ^~~~~~~~~~~
> include/linux/minmax.h:42:24: note: in expansion of macro '__safe_cmp'
> 42 | __builtin_choose_expr(__safe_cmp(x, y), \
> | ^~~~~~~~~~
> include/linux/minmax.h:58:19: note: in expansion of macro '__careful_cmp'
> 58 | #define max(x, y) __careful_cmp(x, y, >)
> | ^~~~~~~~~~~~~
> arch/arm/include/asm/efi.h:74:25: note: in expansion of macro 'max'
> 74 | #define EFI_PHYS_ALIGN max(SZ_2M, roundup_pow_of_two(TEXT_OFFSET))
> | ^~~
> drivers/firmware/efi/libstub/arm32-stub.c:123:44: note: in expansion of macro 'EFI_PHYS_ALIGN'
> 123 | int alloc_size = MAX_UNCOMP_KERNEL_SIZE + EFI_PHYS_ALIGN;
> | ^~~~~~~~~~~~~~
...

Thanks for the report. I actually spotted this and sent a fix
yesterday [0]. I'll send it to -tip today.

[0] https://lore.kernel.org/linux-efi/20201213151306.73558-1-ardb@kernel.org/