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* xilinx_uartps.c: suppress "may be used uninitialised" warning
@ 2019-07-31  6:05 ` Stephen Rothwell
  0 siblings, 0 replies; 3+ messages in thread
From: Stephen Rothwell @ 2019-07-31  6:05 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Linux PPC Development List, Linux Next Mailing List,
	Linux Kernel Mailing List, Jiri Slaby, Michal Simek,
	Linux Serial List, Linus ARM List

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From 31753a44c62c4fdf6e8a72994ae6861dbde49c11 Mon Sep 17 00:00:00 2001
From: Stephen Rothwell <sfr@canb.auug.org.au>
Date: Wed, 31 Jul 2019 16:00:52 +1000
Subject: [PATCH] xilinx_uartps.c: suppress "may be used uninitialised" warning

A powerpc allyesconfig build produces this warning:

In file included from include/linux/radix-tree.h:16,
                 from include/linux/idr.h:15,
                 from include/linux/kernfs.h:13,
                 from include/linux/sysfs.h:16,
                 from include/linux/kobject.h:20,
                 from include/linux/device.h:16,
                 from include/linux/platform_device.h:13,
                 from drivers/tty/serial/xilinx_uartps.c:16:
drivers/tty/serial/xilinx_uartps.c: In function 'cdns_uart_console_write':
include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
   _raw_spin_unlock_irqrestore(lock, flags); \
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/tty/serial/xilinx_uartps.c:1197:16: note: 'flags' was declared here
  unsigned long flags;
                ^~~~~

It looks like gcc just can't track the relationship between "locked"
and "flags", and it is obvious that "flags" won't be used when "locked"
is zero, so the simplest thing is to initialise flags.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
---
 drivers/tty/serial/xilinx_uartps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

This has been like this for a very long time, but this is now one of
the few remaining warnings produced by the powerpc allyesconfig build,
so it would be good to get rid of it.

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index f145946f659b..da4563aaaf5c 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1194,7 +1194,7 @@ static void cdns_uart_console_write(struct console *co, const char *s,
 				unsigned int count)
 {
 	struct uart_port *port = console_port;
-	unsigned long flags;
+	unsigned long flags = 0;
 	unsigned int imr, ctrl;
 	int locked = 1;
 
-- 
2.22.0

-- 
Cheers,
Stephen Rothwell

[-- Attachment #2: OpenPGP digital signature --]
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^ permalink raw reply related	[flat|nested] 3+ messages in thread

* xilinx_uartps.c: suppress "may be used uninitialised" warning
@ 2019-07-31  6:05 ` Stephen Rothwell
  0 siblings, 0 replies; 3+ messages in thread
From: Stephen Rothwell @ 2019-07-31  6:05 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Michal Simek, Linux Kernel Mailing List, Linux Next Mailing List,
	Linux Serial List, Jiri Slaby, Linux PPC Development List,
	Linus ARM List

[-- Attachment #1: Type: text/plain, Size: 2311 bytes --]

From 31753a44c62c4fdf6e8a72994ae6861dbde49c11 Mon Sep 17 00:00:00 2001
From: Stephen Rothwell <sfr@canb.auug.org.au>
Date: Wed, 31 Jul 2019 16:00:52 +1000
Subject: [PATCH] xilinx_uartps.c: suppress "may be used uninitialised" warning

A powerpc allyesconfig build produces this warning:

In file included from include/linux/radix-tree.h:16,
                 from include/linux/idr.h:15,
                 from include/linux/kernfs.h:13,
                 from include/linux/sysfs.h:16,
                 from include/linux/kobject.h:20,
                 from include/linux/device.h:16,
                 from include/linux/platform_device.h:13,
                 from drivers/tty/serial/xilinx_uartps.c:16:
drivers/tty/serial/xilinx_uartps.c: In function 'cdns_uart_console_write':
include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
   _raw_spin_unlock_irqrestore(lock, flags); \
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/tty/serial/xilinx_uartps.c:1197:16: note: 'flags' was declared here
  unsigned long flags;
                ^~~~~

It looks like gcc just can't track the relationship between "locked"
and "flags", and it is obvious that "flags" won't be used when "locked"
is zero, so the simplest thing is to initialise flags.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
---
 drivers/tty/serial/xilinx_uartps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

This has been like this for a very long time, but this is now one of
the few remaining warnings produced by the powerpc allyesconfig build,
so it would be good to get rid of it.

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index f145946f659b..da4563aaaf5c 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1194,7 +1194,7 @@ static void cdns_uart_console_write(struct console *co, const char *s,
 				unsigned int count)
 {
 	struct uart_port *port = console_port;
-	unsigned long flags;
+	unsigned long flags = 0;
 	unsigned int imr, ctrl;
 	int locked = 1;
 
-- 
2.22.0

-- 
Cheers,
Stephen Rothwell

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* xilinx_uartps.c: suppress "may be used uninitialised" warning
@ 2019-07-31  6:05 ` Stephen Rothwell
  0 siblings, 0 replies; 3+ messages in thread
From: Stephen Rothwell @ 2019-07-31  6:05 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: Michal Simek, Linux Kernel Mailing List, Linux Next Mailing List,
	Linux Serial List, Jiri Slaby, Linux PPC Development List,
	Linus ARM List


[-- Attachment #1.1: Type: text/plain, Size: 2311 bytes --]

From 31753a44c62c4fdf6e8a72994ae6861dbde49c11 Mon Sep 17 00:00:00 2001
From: Stephen Rothwell <sfr@canb.auug.org.au>
Date: Wed, 31 Jul 2019 16:00:52 +1000
Subject: [PATCH] xilinx_uartps.c: suppress "may be used uninitialised" warning

A powerpc allyesconfig build produces this warning:

In file included from include/linux/radix-tree.h:16,
                 from include/linux/idr.h:15,
                 from include/linux/kernfs.h:13,
                 from include/linux/sysfs.h:16,
                 from include/linux/kobject.h:20,
                 from include/linux/device.h:16,
                 from include/linux/platform_device.h:13,
                 from drivers/tty/serial/xilinx_uartps.c:16:
drivers/tty/serial/xilinx_uartps.c: In function 'cdns_uart_console_write':
include/linux/spinlock.h:288:3: warning: 'flags' may be used uninitialized in this function [-Wmaybe-uninitialized]
   _raw_spin_unlock_irqrestore(lock, flags); \
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/tty/serial/xilinx_uartps.c:1197:16: note: 'flags' was declared here
  unsigned long flags;
                ^~~~~

It looks like gcc just can't track the relationship between "locked"
and "flags", and it is obvious that "flags" won't be used when "locked"
is zero, so the simplest thing is to initialise flags.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
---
 drivers/tty/serial/xilinx_uartps.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

This has been like this for a very long time, but this is now one of
the few remaining warnings produced by the powerpc allyesconfig build,
so it would be good to get rid of it.

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index f145946f659b..da4563aaaf5c 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1194,7 +1194,7 @@ static void cdns_uart_console_write(struct console *co, const char *s,
 				unsigned int count)
 {
 	struct uart_port *port = console_port;
-	unsigned long flags;
+	unsigned long flags = 0;
 	unsigned int imr, ctrl;
 	int locked = 1;
 
-- 
2.22.0

-- 
Cheers,
Stephen Rothwell

[-- Attachment #1.2: OpenPGP digital signature --]
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[-- Attachment #2: Type: text/plain, Size: 176 bytes --]

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^ permalink raw reply related	[flat|nested] 3+ messages in thread

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2019-07-31  6:05 xilinx_uartps.c: suppress "may be used uninitialised" warning Stephen Rothwell
2019-07-31  6:05 ` Stephen Rothwell
2019-07-31  6:05 ` Stephen Rothwell

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