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>

4 files changed, 5 insertions, 5 deletions

diff --git a/drivers/mtd/nand/raw/nand_ecc.c b/drivers/mtd/nand/raw/nand_ecc.c
index 09fdced659f5..b6a46b1b7781 100644
--- a/drivers/mtd/nand/raw/nand_ecc.c
+++ b/drivers/mtd/nand/raw/nand_ecc.c
@@ -131,7 +131,7 @@ void __nand_calculate_ecc(const unsigned char *buf, unsigned int eccsize,
 	/* rp0..rp15..rp17 are the various accumulated parities (per byte) */
 	uint32_t rp0, rp1, rp2, rp3, rp4, rp5, rp6, rp7;
 	uint32_t rp8, rp9, rp10, rp11, rp12, rp13, rp14, rp15, rp16;
-	uint32_t uninitialized_var(rp17);	/* to make compiler happy */
+	uint32_t rp17;
 	uint32_t par;		/* the cumulative parity for all data */
 	uint32_t tmppar;	/* the cumulative parity for this iteration;
 				   for rp12, rp14 and rp16 at the end of the
diff --git a/drivers/mtd/nand/raw/s3c2410.c b/drivers/mtd/nand/raw/s3c2410.c
index f86dff311464..d0dd0c446e4d 100644
--- a/drivers/mtd/nand/raw/s3c2410.c
+++ b/drivers/mtd/nand/raw/s3c2410.c
@@ -291,7 +291,7 @@ static int s3c2410_nand_setrate(struct s3c2410_nand_info *info)
 	int tacls_max = (info->cpu_type == TYPE_S3C2412) ? 8 : 4;
 	int tacls, twrph0, twrph1;
 	unsigned long clkrate = clk_get_rate(info->clk);
-	unsigned long uninitialized_var(set), cfg, uninitialized_var(mask);
+	unsigned long set, cfg, mask;
 	unsigned long flags;
 
 	/* calculate the timing information for the controller */
diff --git a/drivers/mtd/parsers/afs.c b/drivers/mtd/parsers/afs.c
index 752b6cf005f7..980e332bdac4 100644
--- a/drivers/mtd/parsers/afs.c
+++ b/drivers/mtd/parsers/afs.c
@@ -126,8 +126,8 @@ static int afs_parse_v1_partition(struct mtd_info *mtd,
 	 * Static checks cannot see that we bail out if we have an error
 	 * reading the footer.
 	 */
-	u_int uninitialized_var(iis_ptr);
-	u_int uninitialized_var(img_ptr);
+	u_int iis_ptr;
+	u_int img_ptr;
 	u_int ptr;
 	size_t sz;
 	int ret;
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index 5133e1be5331..0edecfdbd01f 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -599,7 +599,7 @@ int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum,
 	int err, pnum, scrub = 0, vol_id = vol->vol_id;
 	struct ubi_vid_io_buf *vidb;
 	struct ubi_vid_hdr *vid_hdr;
-	uint32_t uninitialized_var(crc);
+	uint32_t crc;
 
 	err = leb_read_lock(ubi, vol_id, lnum);
 	if (err)