make W=1 generates the following warning in page_mapping() for allnoconfig mm/util.c:700:15: warning: variable ‘entry’ set but not used [-Wunused-but-set-variable] swp_entry_t entry; ^~~~~ swap_address is a #define on !CONFIG_SWAP configurations. Make the helper an inline function to suppress the warning, add type checking and to apply any side-effects in the parameter list. Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> --- include/linux/swap.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/include/linux/swap.h b/include/linux/swap.h index 144727041e78..216462c78a91 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -526,7 +526,11 @@ static inline struct swap_info_struct *swp_swap_info(swp_entry_t entry) return NULL; } -#define swap_address_space(entry) (NULL) +static inline struct address_space *swap_address_space(swp_entry_t entry) +{ + return NULL; +} + #define get_nr_swap_pages() 0L #define total_swap_pages 0L #define total_swapcache_pages() 0UL -- 2.26.2