fix warning of uninitialized 'base' in arch/x86/kernel/scx200_32.c
arch/x86/kernel/scx200_32.c: In function ‘scx200_probe’:
arch/x86/kernel/scx200_32.c:82: warning: ‘base’ may be used
uninitialized in this function
Signed-off-by: Jianjun Kong <[email protected]>
---
arch/x86/kernel/scx200_32.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/arch/x86/kernel/scx200_32.c b/arch/x86/kernel/scx200_32.c
index 7e004ac..e9e3a24 100644
--- a/arch/x86/kernel/scx200_32.c
+++ b/arch/x86/kernel/scx200_32.c
@@ -58,7 +58,7 @@ static void __devinit scx200_init_shadow(void)
static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
- unsigned base;
+ unsigned base = 0;
if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE ||
pdev->device == PCI_DEVICE_ID_NS_SC1100_BRIDGE) {
--
1.5.6.3
--
Jianjun Kong | Happy Hacking
HOMEPAGE: http://kongove.cn/
GTALK: [email protected]
* Jianjun Kong <[email protected]> wrote:
> fix warning of uninitialized 'base' in arch/x86/kernel/scx200_32.c
>
> arch/x86/kernel/scx200_32.c: In function ‘scx200_probe’:
> arch/x86/kernel/scx200_32.c:82: warning: ‘base’ may be used
> uninitialized in this function
>
> Signed-off-by: Jianjun Kong <[email protected]>
> ---
> arch/x86/kernel/scx200_32.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
this patch is wrong, and your analysis-free commit log is wrong as well!
i fixed this a few weeks ago, and GCC pinpointed a _real_ bug - which you
hacked around instead of fixing. See the real fix below.
Ingo
---------------------->
>From 6f9fecb3d70400c5f99c1a1d09ffcce84483f611 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <[email protected]>
Date: Sat, 18 Oct 2008 17:37:39 +0200
Subject: [PATCH] fix warning in arch/x86/kernel/scx200_32.c
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
fix this warning:
arch/x86/kernel/scx200_32.c: In function ‘scx200_probe’:
arch/x86/kernel/scx200_32.c:82: warning: ‘base’ may be used uninitialized in this function
gcc is right: pci_read_config_dword() can fail, and this code did not
handle it.
Add proper error handling.
Signed-off-by: Ingo Molnar <[email protected]>
---
arch/x86/kernel/scx200_32.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/scx200_32.c b/arch/x86/kernel/scx200_32.c
index 7e004ac..1b6e3d1 100644
--- a/arch/x86/kernel/scx200_32.c
+++ b/arch/x86/kernel/scx200_32.c
@@ -78,8 +78,10 @@ static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_
if (scx200_cb_probe(SCx200_CB_BASE_FIXED)) {
scx200_cb_base = SCx200_CB_BASE_FIXED;
} else {
- pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
- if (scx200_cb_probe(base)) {
+ int err;
+
+ err = pci_read_config_dword(pdev, SCx200_CBA_SCRATCH, &base);
+ if (!err && scx200_cb_probe(base)) {
scx200_cb_base = base;
} else {
printk(KERN_WARNING NAME ": Configuration Block not found\n");
* Ingo Molnar <[email protected]> wrote:
>
> * Jianjun Kong <[email protected]> wrote:
>
> > fix warning of uninitialized 'base' in arch/x86/kernel/scx200_32.c
> >
> > arch/x86/kernel/scx200_32.c: In function ‘scx200_probe’:
> > arch/x86/kernel/scx200_32.c:82: warning: ‘base’ may be used
> > uninitialized in this function
> >
> > Signed-off-by: Jianjun Kong <[email protected]>
> > ---
> > arch/x86/kernel/scx200_32.c | 2 +-
> > 1 files changed, 1 insertions(+), 1 deletions(-)
>
> this patch is wrong, and your analysis-free commit log is wrong as
> well!
>
> i fixed this a few weeks ago, and GCC pinpointed a _real_ bug - which
> you hacked around instead of fixing. See the real fix below.
Also, see an example below of the case where GCC is wrong about a
warning, and how it is annotated.
Ingo
------------->
>From af4d2994e0e8e6e529b0e87f4e436dad062a9c05 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <[email protected]>
Date: Tue, 25 Nov 2008 13:14:19 +0100
Subject: [PATCH] fix warning in fs/ocfs2/stack_user.c
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
this warning:
fs/ocfs2/stack_user.c: In function ‘user_cluster_connect’:
fs/ocfs2/stack_user.c:807: warning: ‘control’ may be used uninitialized in this function
triggers because GCC does not recognize the (correct) error flow
between:
- ocfs2_live_connection_new() and 'control'
Annotate it.
Signed-off-by: Ingo Molnar <[email protected]>
---
fs/ocfs2/stack_user.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c
index faec2d8..55e2cdc 100644
--- a/fs/ocfs2/stack_user.c
+++ b/fs/ocfs2/stack_user.c
@@ -804,7 +804,7 @@ static int fs_protocol_compare(struct ocfs2_protocol_version *existing,
static int user_cluster_connect(struct ocfs2_cluster_connection *conn)
{
dlm_lockspace_t *fsdlm;
- struct ocfs2_live_connection *control;
+ struct ocfs2_live_connection *uninitialized_var(control);
int rc = 0;
BUG_ON(conn == NULL);