On 12/09/2013 11:36 PM, Seth Jennings wrote: > On Mon, Dec 09, 2013 at 10:51:16AM +0800, Chen Gang wrote: >> Recommend to add default case to avoid compiler's warning, although at >> present, the original implementation is still correct. >> >> The related warning (with allmodconfig for metag): >> >> CC mm/zswap.o >> mm/zswap.c: In function 'zswap_writeback_entry': >> mm/zswap.c:537: warning: 'ret' may be used uninitialized in this function >> >> >> Signed-off-by: Chen Gang <gang.chen.5i5j@xxxxxxxxx> >> --- >> mm/zswap.c | 2 ++ >> 1 files changed, 2 insertions(+), 0 deletions(-) >> >> diff --git a/mm/zswap.c b/mm/zswap.c >> index 5a63f78..bfd1807 100644 >> --- a/mm/zswap.c >> +++ b/mm/zswap.c >> @@ -585,6 +585,8 @@ static int zswap_writeback_entry(struct zbud_pool *pool, unsigned long handle) >> >> /* page is up to date */ >> SetPageUptodate(page); >> + default: >> + BUG(); > > Typically, the way you want to address this is initialize ret to 0 > at declaration time if not every control path will set that value. > At least, your suggestion sounds reasonable. But I am also aware that normally need content 'default' for 'switch', so I choose this fix way. And sorry, current patch is incorrect (need 'break' before 'default'), so if no additional suggestions or discussions or completions, I will/should send patch v2 for it. Thanks. -- Chen Gang Open, share, and attitude like air, water and life which God blessed -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>