[PATCH] autofs4 - fix false positive compile error

[PATCH] autofs4 - fix false positive compile error

[Ian Kent]

On strict build environments we can see:

fs/autofs4/inode.c: In function 'autofs4_fill_super':
fs/autofs4/inode.c:312: error: 'pgrp' may be used uninitialized in this
function
make[2]: *** [fs/autofs4/inode.o] Error 1
make[1]: *** [fs/autofs4] Error 2
make: *** [fs] Error 2
make: *** Waiting for unfinished jobs....

This is due to the use of pgrp_set being used to indicate pgrp has
has been set rather than initializing pgrp itself.

Signed-off-by: Ian Kent <raven@themaw.net>
---
 fs/autofs4/inode.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index d7bd395..1c55388 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -210,7 +210,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
 	int pipefd;
 	struct autofs_sb_info *sbi;
 	struct autofs_info *ino;
-	int pgrp;
+	int pgrp = 0;
 	bool pgrp_set = false;
 	int ret = -EINVAL;
 

Re: [PATCH] autofs4 - fix false positive compile error

[Andrew Morton]

On Wed, 25 Jun 2014 20:49:39 +0800 Ian Kent <raven@themaw.net> wrote:

> On strict build environments we can see:
> 
> fs/autofs4/inode.c: In function 'autofs4_fill_super':
> fs/autofs4/inode.c:312: error: 'pgrp' may be used uninitialized in this
> function
> make[2]: *** [fs/autofs4/inode.o] Error 1
> make[1]: *** [fs/autofs4] Error 2
> make: *** [fs] Error 2
> make: *** Waiting for unfinished jobs....
> 
> This is due to the use of pgrp_set being used to indicate pgrp has
> has been set rather than initializing pgrp itself.
> 

Yes, that code seems to be explicitly designed to trigger a gcc warning ;)

What is a "strict build environment"?  Someone's using -Werror for the
entire kernel?  That must make for a miserable life.

Re: [PATCH] autofs4 - fix false positive compile error

[Ian Kent]

On Wed, 2014-06-25 at 13:06 -0700, Andrew Morton wrote:
> On Wed, 25 Jun 2014 20:49:39 +0800 Ian Kent <raven@themaw.net> wrote:
> 
> > On strict build environments we can see:
> > 
> > fs/autofs4/inode.c: In function 'autofs4_fill_super':
> > fs/autofs4/inode.c:312: error: 'pgrp' may be used uninitialized in this
> > function
> > make[2]: *** [fs/autofs4/inode.o] Error 1
> > make[1]: *** [fs/autofs4] Error 2
> > make: *** [fs] Error 2
> > make: *** Waiting for unfinished jobs....
> > 
> > This is due to the use of pgrp_set being used to indicate pgrp has
> > has been set rather than initializing pgrp itself.
> > 
> 
> Yes, that code seems to be explicitly designed to trigger a gcc warning ;)
> 
> What is a "strict build environment"?  Someone's using -Werror for the
> entire kernel?  That must make for a miserable life.

Yes, TBH I was a bit surprised myself.
It resulted from a RHEL-6.6 patch submission.

I didn't notice it and ended up missing an internal (RedHat) patch
submission deadline as my original interest in these was the result of
an upstream discussion and I stupidly relied on my upstream testing.

It might just be that our internal up and coming file system tree is
specifically more fussy but never the less I got caught out.

Ian