From: Paul E. McKenney Date: Mon, 9 Mar 2015 23:51:17 +0000 (-0700) Subject: rcu: Shut up spurious gcc uninitialized-variable warning X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=3eaaaf6cd6d7fbaf552cc543ccb93d7da81f43ec;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git rcu: Shut up spurious gcc uninitialized-variable warning Because gcc doesn't realize that rcu_num_lvls must be strictly greater than zero, some versions give a spurious warning about levelcnt[0] being uninitialized in rcu_init_one(). This commit updates the condition on the pre-existing panic() in order to educate gcc on this point. Signed-off-by: Paul E. McKenney --- diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index c34422d92aa9..9b076b284695 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3982,9 +3982,9 @@ static void __init rcu_init_one(struct rcu_state *rsp, BUILD_BUG_ON(MAX_RCU_LVLS > ARRAY_SIZE(buf)); /* Fix buf[] init! */ - /* Silence gcc 4.8 warning about array index out of range. */ - if (rcu_num_lvls > RCU_NUM_LVLS) - panic("rcu_init_one: rcu_num_lvls overflow"); + /* Silence gcc 4.8 false positive about array index out of range. */ + if (rcu_num_lvls <= 0 || rcu_num_lvls > RCU_NUM_LVLS) + panic("rcu_init_one: rcu_num_lvls out of range"); /* Initialize the level-tracking arrays. */