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>
diff --git a/kernel/async.c b/kernel/async.c
index 4f9c1d6..33258e6 100644
--- a/kernel/async.c
+++ b/kernel/async.c
@@ -111,7 +111,7 @@
struct async_entry *entry =
container_of(work, struct async_entry, work);
unsigned long flags;
- ktime_t uninitialized_var(calltime), delta, rettime;
+ ktime_t calltime, delta, rettime;
/* 1) run (and print duration) */
if (initcall_debug && system_state < SYSTEM_RUNNING) {
@@ -287,7 +287,7 @@
*/
void async_synchronize_cookie_domain(async_cookie_t cookie, struct async_domain *domain)
{
- ktime_t uninitialized_var(starttime), delta, endtime;
+ ktime_t starttime, delta, endtime;
if (initcall_debug && system_state < SYSTEM_RUNNING) {
pr_debug("async_waiting @ %i\n", task_pid_nr(current));
diff --git a/kernel/audit.c b/kernel/audit.c
index 8c201f4..ec38479 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1800,7 +1800,7 @@
{
struct audit_buffer *ab;
struct timespec64 t;
- unsigned int uninitialized_var(serial);
+ unsigned int serial;
if (audit_initialized != AUDIT_INITIALIZED)
return NULL;
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index 683a799..9d847ab 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -591,7 +591,7 @@
int this_cpu, old_cpu;
char *cp, *cp2, *cphold = NULL, replaced_byte = ' ';
char *moreprompt = "more> ";
- unsigned long uninitialized_var(flags);
+ unsigned long flags;
/* Serialize kdb_printf if multiple cpus try to write at once.
* But if any cpu goes recursive in kdb, just print the output,
diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 36c962a..d628ab09 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -882,7 +882,7 @@
static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data)
{
struct device *dev = data;
- struct dma_debug_entry *uninitialized_var(entry);
+ struct dma_debug_entry *entry;
int count;
if (dma_debug_disabled())
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 856d98c..851fc5e 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -11483,7 +11483,7 @@
struct perf_event *group_leader = NULL, *output_event = NULL;
struct perf_event *event, *sibling;
struct perf_event_attr attr;
- struct perf_event_context *ctx, *uninitialized_var(gctx);
+ struct perf_event_context *ctx, *gctx;
struct file *event_file = NULL;
struct fd group = {NULL, 0};
struct task_struct *task = NULL;
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index bb08628..e84eb52 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -2189,7 +2189,7 @@
{
struct uprobe *uprobe;
unsigned long bp_vaddr;
- int uninitialized_var(is_swbp);
+ int is_swbp;
bp_vaddr = uprobe_get_swbp_addr(regs);
if (bp_vaddr == get_trampoline_vaddr())
diff --git a/kernel/exit.c b/kernel/exit.c
index 727150f..7bcd571 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -93,7 +93,7 @@
struct signal_struct *sig = tsk->signal;
bool group_dead = thread_group_leader(tsk);
struct sighand_struct *sighand;
- struct tty_struct *uninitialized_var(tty);
+ struct tty_struct *tty;
u64 utime, stime;
sighand = rcu_dereference_check(tsk->sighand,
diff --git a/kernel/futex.c b/kernel/futex.c
index e646661..05e8856 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1326,7 +1326,7 @@
static int lock_pi_update_atomic(u32 __user *uaddr, u32 uval, u32 newval)
{
int err;
- u32 uninitialized_var(curval);
+ u32 curval;
if (unlikely(should_fail_futex(true)))
return -EFAULT;
@@ -1496,7 +1496,7 @@
*/
static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_state)
{
- u32 uninitialized_var(curval), newval;
+ u32 curval, newval;
struct task_struct *new_owner;
bool postunlock = false;
DEFINE_WAKE_Q(wake_q);
@@ -2370,7 +2370,7 @@
struct task_struct *argowner)
{
struct futex_pi_state *pi_state = q->pi_state;
- u32 uval, uninitialized_var(curval), newval;
+ u32 uval, curval, newval;
struct task_struct *oldowner, *newowner;
u32 newtid;
int ret, err = 0;
@@ -2996,7 +2996,7 @@
*/
static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags)
{
- u32 uninitialized_var(curval), uval, vpid = task_pid_vnr(current);
+ u32 curval, uval, vpid = task_pid_vnr(current);
union futex_key key = FUTEX_KEY_INIT;
struct futex_hash_bucket *hb;
struct futex_q *top_waiter;
@@ -3479,7 +3479,7 @@
static int handle_futex_death(u32 __user *uaddr, struct task_struct *curr,
bool pi, bool pending_op)
{
- u32 uval, uninitialized_var(nval), mval;
+ u32 uval, nval, mval;
int err;
/* Futex address must be 32bit aligned */
@@ -3609,7 +3609,7 @@
struct robust_list_head __user *head = curr->robust_list;
struct robust_list __user *entry, *next_entry, *pending;
unsigned int limit = ROBUST_LIST_LIMIT, pi, pip;
- unsigned int uninitialized_var(next_pi);
+ unsigned int next_pi;
unsigned long futex_offset;
int rc;
@@ -3909,7 +3909,7 @@
struct compat_robust_list_head __user *head = curr->compat_robust_list;
struct robust_list __user *entry, *next_entry, *pending;
unsigned int limit = ROBUST_LIST_LIMIT, pi, pip;
- unsigned int uninitialized_var(next_pi);
+ unsigned int next_pi;
compat_uptr_t uentry, next_uentry, upending;
compat_long_t futex_offset;
int rc;
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 29a8de4..84ed1d1 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1723,7 +1723,7 @@
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 @@
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 @@
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 @@
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 @@
{
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 @@
{
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 @@
{
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);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 00867ff..f15471c 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -577,7 +577,7 @@
*/
int ring_buffer_wait(struct trace_buffer *buffer, int cpu, int full)
{
- struct ring_buffer_per_cpu *uninitialized_var(cpu_buffer);
+ struct ring_buffer_per_cpu *cpu_buffer;
DEFINE_WAIT(wait);
struct rb_irq_work *work;
int ret = 0;