treewide: Remove uninitialized_var() usage

Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>

1 files changed, 8 insertions, 8 deletions

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 29a8de4c50b9..84ed1d1d5013 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1723,7 +1723,7 @@ static int noop_count(struct lock_list *entry, void *data)
 static unsigned long __lockdep_count_forward_deps(struct lock_list *this)
 {
 	unsigned long  count = 0;
-	struct lock_list *uninitialized_var(target_entry);
+	struct lock_list *target_entry;
 
 	__bfs_forwards(this, (void *)&count, noop_count, &target_entry);
 
@@ -1749,7 +1749,7 @@ unsigned long lockdep_count_forward_deps(struct lock_class *class)
 static unsigned long __lockdep_count_backward_deps(struct lock_list *this)
 {
 	unsigned long  count = 0;
-	struct lock_list *uninitialized_var(target_entry);
+	struct lock_list *target_entry;
 
 	__bfs_backwards(this, (void *)&count, noop_count, &target_entry);
 
@@ -1804,7 +1804,7 @@ check_noncircular(struct held_lock *src, struct held_lock *target,
 		  struct lock_trace **const trace)
 {
 	int ret;
-	struct lock_list *uninitialized_var(target_entry);
+	struct lock_list *target_entry;
 	struct lock_list src_entry = {
 		.class = hlock_class(src),
 		.parent = NULL,
@@ -1842,7 +1842,7 @@ static noinline int
 check_redundant(struct held_lock *src, struct held_lock *target)
 {
 	int ret;
-	struct lock_list *uninitialized_var(target_entry);
+	struct lock_list *target_entry;
 	struct lock_list src_entry = {
 		.class = hlock_class(src),
 		.parent = NULL,
@@ -2244,8 +2244,8 @@ static int check_irq_usage(struct task_struct *curr, struct held_lock *prev,
 {
 	unsigned long usage_mask = 0, forward_mask, backward_mask;
 	enum lock_usage_bit forward_bit = 0, backward_bit = 0;
-	struct lock_list *uninitialized_var(target_entry1);
-	struct lock_list *uninitialized_var(target_entry);
+	struct lock_list *target_entry1;
+	struct lock_list *target_entry;
 	struct lock_list this, that;
 	int ret;
 
@@ -3438,7 +3438,7 @@ check_usage_forwards(struct task_struct *curr, struct held_lock *this,
 {
 	int ret;
 	struct lock_list root;
-	struct lock_list *uninitialized_var(target_entry);
+	struct lock_list *target_entry;
 
 	root.parent = NULL;
 	root.class = hlock_class(this);
@@ -3465,7 +3465,7 @@ check_usage_backwards(struct task_struct *curr, struct held_lock *this,
 {
 	int ret;
 	struct lock_list root;
-	struct lock_list *uninitialized_var(target_entry);
+	struct lock_list *target_entry;
 
 	root.parent = NULL;
 	root.class = hlock_class(this);