clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

PATCH New Boris Brezillon 5 participants 8 messages Dec 12, 2016

Subsystems (3)

Common clk Broadcom BCM2711/BCM2835 Arm architecture Broadcom BCM281XX/BCM11XXX/BCM216XX Arm architecture

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Boris Brezillon

author

2016-12-12 08:00 UTC #0 lore raw

PATCH 1/1 clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

best_rate is reported as potentially uninitialized by gcc.

Signed-off-by Boris Brezillon <[email protected]>

Fixes 155e8b3b0ee3 ("clk: bcm: Support rate change propagation on bcm2835 clocks")

Reported-by Stephen Rothwell <[email protected]>

---
 drivers/clk/bcm/clk-bcm2835.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

drivers/clk/bcm/clk-bcm2835.c +1 -1

index eaf82f49dede..0d14409097e7 100644
@@ -1029,7 +1029,7 @@ static unsigned long bcm2835_clock_choose_div_and_prate(struct clk_hw *hw,
 	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
 	struct bcm2835_cprman *cprman = clock->cprman;
 	const struct bcm2835_clock_data *data = clock->data;
-	unsigned long best_rate;
+	unsigned long best_rate = 0;
 	u32 curdiv, mindiv, maxdiv;
 	struct clk_hw *parent;

Signature · 1 line

2.7.4

Arnd Bergmann

2016-12-12 08:12 UTC #1 lore raw

PATCH 1/1 clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

Quoted 5 lines · CET Boris Brezillon

best_rate is reported as potentially uninitialized by gcc.
Signed-off-by Boris Brezillon <[email protected]>
Fixes 155e8b3b0ee3 ("clk: bcm: Support rate change propagation on bcm2835 clocks")
Reported-by Stephen Rothwell <[email protected]>

I wonder why I didn't get that. Which compiler version did you use?

Arnd

Stephen Rothwell

2016-12-12 08:22 UTC #2 lore raw

PATCH 1/1 clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

Hi Arnd,

Quoted 9 lines · On Mon, 12 Dec 2016 09:12:36 +0100 Arnd Bergmann <[email protected]> wrote:

Quoted 5 lines · CET Boris Brezillon
best_rate is reported as potentially uninitialized by gcc.
Signed-off-by Boris Brezillon <[email protected]>
Fixes 155e8b3b0ee3 ("clk: bcm: Support rate change propagation on bcm2835 clocks")
Reported-by Stephen Rothwell <[email protected]>
I wonder why I didn't get that. Which compiler version did you use?

Gcc-5.2.0 powerpc-le hosted cross compiler.

Signature · 2 lines

Cheers,
Stephen Rothwell

Boris Brezillon

author

2016-12-12 08:31 UTC #3 lore raw

PATCH 1/1 clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

In reply to Arnd Bergmann

Quoted 9 lines · On Mon, 12 Dec 2016 09:12:36 +0100 Arnd Bergmann <[email protected]> wrote:

Quoted 5 lines · CET Boris Brezillon
best_rate is reported as potentially uninitialized by gcc.
Signed-off-by Boris Brezillon <[email protected]>
Fixes 155e8b3b0ee3 ("clk: bcm: Support rate change propagation on bcm2835 clocks")
Reported-by Stephen Rothwell <[email protected]>
I wonder why I didn't get that. Which compiler version did you use?

In case you're interested, my gcc [1] failed to detect it as well, and this is not the first time it happens :-/.

[1]gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609

Arnd Bergmann

2016-12-12 08:34 UTC #4 lore raw

PATCH 1/1 clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

Quoted 10 lines · CET Boris Brezillon

Quoted 7 lines · On Mon, 12 Dec 2016 09:12:36 +0100 Arnd Bergmann <[email protected]> wrote:
Quoted 5 lines · CET Boris Brezillon
best_rate is reported as potentially uninitialized by gcc.
Signed-off-by Boris Brezillon <[email protected]>
Fixes 155e8b3b0ee3 ("clk: bcm: Support rate change propagation on bcm2835 clocks")
Reported-by Stephen Rothwell <[email protected]>

Quoted 7 lines

Quoted 2 lines
I wonder why I didn't get that. Which compiler version did you use?
In case you're interested, my gcc [1] failed to detect it as well, and this is not the first time it happens :-/.
[1]gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609

No, I see it now with gcc-7, it only just turned up in linux-next.

I ran into it right away with an allmodconfig build. You were probably testing based on an earlier v4.9-rc release that had the warning globally disabled.

Arnd

Boris Brezillon

author

2016-12-12 09:03 UTC #5 lore raw

PATCH 1/1 clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

Quoted 17 lines · On Mon, 12 Dec 2016 09:34:28 +0100 Arnd Bergmann <[email protected]> wrote:

Quoted 16 lines · CET Boris Brezillon
Quoted 9 lines · On Mon, 12 Dec 2016 09:12:36 +0100 Arnd Bergmann <[email protected]> wrote:
Quoted 5 lines · CET Boris Brezillon
best_rate is reported as potentially uninitialized by gcc.
Signed-off-by Boris Brezillon <[email protected]>
Fixes 155e8b3b0ee3 ("clk: bcm: Support rate change propagation on bcm2835 clocks")
Reported-by Stephen Rothwell <[email protected]>
I wonder why I didn't get that. Which compiler version did you use?
In case you're interested, my gcc [1] failed to detect it as well, and this is not the first time it happens :-/.

Quoted 7 lines

Quoted 1 line
[1]gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609
No, I see it now with gcc-7, it only just turned up in linux-next.
I ran into it right away with an allmodconfig build. You were probably testing based on an earlier v4.9-rc release that had the warning globally disabled.

Indeed, I was testing on a 4.9-rc.

Eric Anholt

2016-12-12 17:24 UTC #6 lore raw

PATCH 1/1 clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

In reply to Boris Brezillon

Quoted 5 lines · Boris Brezillon

best_rate is reported as potentially uninitialized by gcc.
Signed-off-by Boris Brezillon <[email protected]>
Fixes 155e8b3b0ee3 ("clk: bcm: Support rate change propagation on bcm2835 clocks")
Reported-by Stephen Rothwell <[email protected]>

Reviewed-by Eric Anholt <[email protected]>

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Stephen Boyd

Applied

2016-12-12 19:26 UTC #7 lore raw

PATCH 1/1 clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

In reply to Boris Brezillon

Quoted 6 lines · Boris Brezillon

best_rate is reported as potentially uninitialized by gcc.
Signed-off-by Boris Brezillon <[email protected]>
Fixes 155e8b3b0ee3 ("clk: bcm: Support rate change propagation on bcm2835 clocks")
Reported-by Stephen Rothwell <[email protected]>
---

Applied to clk-next

Signature · 2 lines

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