[PATCH 5.10 02/86] mm: page_alloc: fix building error on -Werror=array-compare

Greg Kroah-Hartman
2022-04-26T08:48:49Z

From: Xiongwei Song <sxwjean@gmail.com>

commit ca831f29f8f25c97182e726429b38c0802200c8f upstream.

Arthur Marsh reported we would hit the error below when building kernel
with gcc-12:

CC mm/page_alloc.o
mm/page_alloc.c: In function `mem_init_print_info':
mm/page_alloc.c:8173:27: error: comparison between two arrays [-Werror=array-compare]
8173 | if (start <= pos && pos < end && size > adj) \
|

In C++20, the comparision between arrays should be warned.

Link: https://lkml.kernel.org/r/20211125130928.32465-1-sxwjean@me.com
Signed-off-by: Xiongwei Song <sxwjean@gmail.com>
Reported-by: Arthur Marsh <arthur.marsh@internode.on.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
mm/page_alloc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -7678,7 +7678,7 @@ void __init mem_init_print_info(const ch
*/
#define adj_init_size(start, end, size, pos, adj) \
do { \
- if (start <= pos && pos < end && size > adj) \
+ if (&start[0] <= &pos[0] && &pos[0] < &end[0] && size > adj) \
size -= adj; \
} while (0)