From: Nathan Chancellor <[email protected]>

[ Upstream commit b0d14fc43d39203ae025f20ef4d5d25d9ccf4be1 ]

Clang warns:

  mm/kmemleak.c:1955:28: warning: array comparison always evaluates to a 
constant [-Wtautological-compare]
        if (__start_ro_after_init < _sdata || __end_ro_after_init > _edata)
                                  ^
  mm/kmemleak.c:1955:60: warning: array comparison always evaluates to a 
constant [-Wtautological-compare]
        if (__start_ro_after_init < _sdata || __end_ro_after_init > _edata)

These are not true arrays, they are linker defined symbols, which are just
addresses.  Using the address of operator silences the warning and does
not change the resulting assembly with either clang/ld.lld or gcc/ld
(tested with diff + objdump -Dr).

Suggested-by: Nick Desaulniers <[email protected]>
Signed-off-by: Nathan Chancellor <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Link: https://github.com/ClangBuiltLinux/linux/issues/895
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
 mm/kmemleak.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 5eeabece0c178..f54734abf9466 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -2039,7 +2039,7 @@ void __init kmemleak_init(void)
        create_object((unsigned long)__bss_start, __bss_stop - __bss_start,
                      KMEMLEAK_GREY, GFP_ATOMIC);
        /* only register .data..ro_after_init if not within .data */
-       if (__start_ro_after_init < _sdata || __end_ro_after_init > _edata)
+       if (&__start_ro_after_init < &_sdata || &__end_ro_after_init > &_edata)
                create_object((unsigned long)__start_ro_after_init,
                              __end_ro_after_init - __start_ro_after_init,
                              KMEMLEAK_GREY, GFP_ATOMIC);
-- 
2.25.1

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