Subject: linux-next: build warning after merge of the mm tree

From: Stephen Rothwell <[email-masked]>
Date: Wed, 25 May 2022 15:54:01 +1000

Hi all,

After merging the mm tree, today's linux-next build (sparc64 defconfig)
produced this warning:

In file included from include/linux/kernel.h:26,
                 from include/linux/cpumask.h:10,
                 from include/linux/smp.h:13,
                 from include/linux/lockdep.h:14,
                 from include/linux/spinlock.h:62,
                 from include/linux/mmzone.h:8,
                 from include/linux/gfp.h:6,
                 from include/linux/mm.h:7,
                 from mm/page_alloc.c:19:
mm/page_alloc.c: In function 'split_free_page':
include/linux/minmax.h:20:35: warning: comparison of distinct pointer types lacks a cast
   20 |         (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
      |                                   ^~
include/linux/minmax.h:26:18: note: in expansion of macro '__typecheck'
   26 |                 (__typecheck(x, y) && __no_side_effects(x, y))
      |                  ^~~~~~~~~~~
include/linux/minmax.h:36:31: note: in expansion of macro '__safe_cmp'
   36 |         __builtin_choose_expr(__safe_cmp(x, y), \
      |                               ^~~~~~~~~~
include/linux/minmax.h:45:25: note: in expansion of macro '__careful_cmp'
   45 | #define min(x, y)       __careful_cmp(x, y, <)
      |                         ^~~~~~~~~~~~~
mm/page_alloc.c:1138:35: note: in expansion of macro 'min'
 1138 |                 free_page_order = min(pfn ? __ffs(pfn) : order, __fls(split_pfn_offset));
      |                                   ^~~

Introduced by commit

  29a8af92b874 ("mm: fix a potential infinite loop in start_isolate_page_range()")

-- 
Cheers,
Stephen Rothwell