mm: fix nodemask printing
authorArnd Bergmann <arnd@arndb.de>
Fri, 17 Nov 2017 23:26:12 +0000 (15:26 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sat, 18 Nov 2017 00:10:00 +0000 (16:10 -0800)
commit1334be3657dd02af0591d6d8adf0e6a60a7710a6
treeb6d61452f00b59f67ade37d5fdba55fc440f4618
parenta3841f94c7ecb3ede0f888d3fcfe8fb6368ddd7a
mm: fix nodemask printing

The cleanup caused build warnings for constant mask pointers:

  mm/mempolicy.c: In function `mpol_to_str':
  ./include/linux/nodemask.h:108:11: warning: the comparison will always evaluate as `true' for the address of `nodes' will never be NULL [-Waddress]

An earlier workaround I suggested was incorporated in the version that
got merged, but that only solved the problem for gcc-7 and higher, while
gcc-4.6 through gcc-6.x still warn.

This changes the printing again to use inline functions that make it
clear to the compiler that the line that does the NULL check has no idea
whether the argument is a constant NULL.

Link: http://lkml.kernel.org/r/20171117101545.119689-1-arnd@arndb.de
Fixes: 0205f75571e3 ("mm: simplify nodemask printing")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Zhangshaokun <zhangshaokun@hisilicon.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/nodemask.h