treewide: Remove uninitialized_var() usage

commit 3f649ab728cda8038259d8f14492fe400fbab911 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/ide/ide-acpi.c b/drivers/ide/ide-acpi.c
index 7d4e5c0..05e18d6 100644
--- a/drivers/ide/ide-acpi.c
+++ b/drivers/ide/ide-acpi.c
@@ -180,7 +180,7 @@ static int ide_get_dev_handle(struct device *dev, acpi_handle *handle,
 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 215558c..3ef1afc 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -591,7 +591,7 @@ 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 1976397..508f98c 100644
--- a/drivers/ide/ide-io-std.c
+++ b/drivers/ide/ide-io-std.c
@@ -172,7 +172,7 @@ 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);
@@ -216,7 +216,7 @@ 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 7f34dc4..70bc469 100644
--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -767,13 +767,13 @@ 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 b9dfeb2..c08a8a0 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 3aa0fea..1414caa 100644
--- a/drivers/ide/umc8672.c
+++ b/drivers/ide/umc8672.c
@@ -107,7 +107,7 @@ 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",