[PATCH 3/3] auxdisplay: img-ascii-lcd: Silence 2 uninitialized warnings

From: Miguel Ojeda
Date: Mon Feb 19 2018 - 11:10:15 EST


The warnings are:

drivers/auxdisplay/img-ascii-lcd.c: warning: 'err' may be used
uninitialized in this function [-Wuninitialized]

At lines 109 and 207. Reported by Geert using the build service
several times, e.g.:

https://lkml.org/lkml/2018/2/19/303

They are two false positives, since num_chars > 0 in the three present
configurations (boston, malta, sead3). Initializing to an error state by
default silences the warning and makes the code print an error in case a
num_chars == 0 happens in the future (unlikely, since it does not make
sense currently).

The warnings seem to disappear starting with gcc >= 4.9

Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Paul Burton <paul.burton@xxxxxxxx>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@xxxxxxxxx>
---
I will queue it up for 4.17.

drivers/auxdisplay/img-ascii-lcd.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/auxdisplay/img-ascii-lcd.c b/drivers/auxdisplay/img-ascii-lcd.c
index d8133024fd5d..bd5ebb5c516c 100644
--- a/drivers/auxdisplay/img-ascii-lcd.c
+++ b/drivers/auxdisplay/img-ascii-lcd.c
@@ -97,7 +97,7 @@ static struct img_ascii_lcd_config boston_config = {
static void malta_update(struct img_ascii_lcd_ctx *ctx)
{
unsigned int i;
- int err;
+ int err = 1;

for (i = 0; i < ctx->cfg->num_chars; i++) {
err = regmap_write(ctx->regmap,
@@ -180,7 +180,7 @@ static int sead3_wait_lcd_idle(struct img_ascii_lcd_ctx *ctx)
static void sead3_update(struct img_ascii_lcd_ctx *ctx)
{
unsigned int i;
- int err;
+ int err = 1;

for (i = 0; i < ctx->cfg->num_chars; i++) {
err = sead3_wait_lcd_idle(ctx);
--
2.14.1