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>

6 files changed, 10 insertions, 10 deletions

diff --git a/drivers/ide/ide-acpi.c b/drivers/ide/ide-acpi.c
index 7d4e5c08f133..05e18d658141 100644
--- a/drivers/ide/ide-acpi.c
+++ b/drivers/ide/ide-acpi.c
@@ -180,7 +180,7 @@ err:
 static acpi_handle ide_acpi_hwif_get_handle(ide_hwif_t *hwif)
 {
 	struct device		*dev = hwif->gendev.parent;
-	acpi_handle		uninitialized_var(dev_handle);
+	acpi_handle		dev_handle;
 	u64			pcidevfn;
 	acpi_handle		chan_handle;
 	int			err;
diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index 80bc3bf82f4d..2162bc80f09e 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -609,7 +609,7 @@ static int ide_delayed_transfer_pc(ide_drive_t *drive)
 
 static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
 {
-	struct ide_atapi_pc *uninitialized_var(pc);
+	struct ide_atapi_pc *pc;
 	ide_hwif_t *hwif = drive->hwif;
 	struct request *rq = hwif->rq;
 	ide_expiry_t *expiry;
diff --git a/drivers/ide/ide-io-std.c b/drivers/ide/ide-io-std.c
index 18c20a7aa0ce..94bdcf1ea186 100644
--- a/drivers/ide/ide-io-std.c
+++ b/drivers/ide/ide-io-std.c
@@ -173,7 +173,7 @@ void ide_input_data(ide_drive_t *drive, struct ide_cmd *cmd, void *buf,
 	u8 mmio = (hwif->host_flags & IDE_HFLAG_MMIO) ? 1 : 0;
 
 	if (io_32bit) {
-		unsigned long uninitialized_var(flags);
+		unsigned long flags;
 
 		if ((io_32bit & 2) && !mmio) {
 			local_irq_save(flags);
@@ -217,7 +217,7 @@ void ide_output_data(ide_drive_t *drive, struct ide_cmd *cmd, void *buf,
 	u8 mmio = (hwif->host_flags & IDE_HFLAG_MMIO) ? 1 : 0;
 
 	if (io_32bit) {
-		unsigned long uninitialized_var(flags);
+		unsigned long flags;
 
 		if ((io_32bit & 2) && !mmio) {
 			local_irq_save(flags);
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
index c31f1d2b3b07..1a53c7a75224 100644
--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -622,12 +622,12 @@ static int drive_is_ready(ide_drive_t *drive)
 void ide_timer_expiry (struct timer_list *t)
 {
 	ide_hwif_t	*hwif = from_timer(hwif, t, timer);
-	ide_drive_t	*uninitialized_var(drive);
+	ide_drive_t	*drive;
 	ide_handler_t	*handler;
 	unsigned long	flags;
 	int		wait = -1;
 	int		plug_device = 0;
-	struct request	*uninitialized_var(rq_in_flight);
+	struct request	*rq_in_flight;
 
 	spin_lock_irqsave(&hwif->lock, flags);
 
@@ -780,13 +780,13 @@ irqreturn_t ide_intr (int irq, void *dev_id)
 {
 	ide_hwif_t *hwif = (ide_hwif_t *)dev_id;
 	struct ide_host *host = hwif->host;
-	ide_drive_t *uninitialized_var(drive);
+	ide_drive_t *drive;
 	ide_handler_t *handler;
 	unsigned long flags;
 	ide_startstop_t startstop;
 	irqreturn_t irq_ret = IRQ_NONE;
 	int plug_device = 0;
-	struct request *uninitialized_var(rq_in_flight);
+	struct request *rq_in_flight;
 
 	if (host->host_flags & IDE_HFLAG_SERIALIZE) {
 		if (hwif != host->cur_port)
diff --git a/drivers/ide/ide-sysfs.c b/drivers/ide/ide-sysfs.c
index b9dfeb2e8bd6..c08a8a0916e2 100644
--- a/drivers/ide/ide-sysfs.c
+++ b/drivers/ide/ide-sysfs.c
@@ -131,7 +131,7 @@ static struct device_attribute *ide_port_attrs[] = {
 
 int ide_sysfs_register_port(ide_hwif_t *hwif)
 {
-	int i, uninitialized_var(rc);
+	int i, rc;
 
 	for (i = 0; ide_port_attrs[i]; i++) {
 		rc = device_create_file(hwif->portdev, ide_port_attrs[i]);
diff --git a/drivers/ide/umc8672.c b/drivers/ide/umc8672.c
index 870e235e30af..cf996f788292 100644
--- a/drivers/ide/umc8672.c
+++ b/drivers/ide/umc8672.c
@@ -108,7 +108,7 @@ static void umc_set_speeds(u8 speeds[])
 static void umc_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
 {
 	ide_hwif_t *mate = hwif->mate;
-	unsigned long uninitialized_var(flags);
+	unsigned long flags;
 	const u8 pio = drive->pio_mode - XFER_PIO_0;
 
 	printk("%s: setting umc8672 to PIO mode%d (speed %d)\n",