Re: [PATCH -mm 1/2] 3c59x: Fix uninitialized variable bug

On Tue, 4 Sep 2007, Mark Hindley wrote:

On Tue, Sep 04, 2007 at 02:09:47PM +0530, Satyam Sharma wrote:

quoted

Hi Steffen,


On Tue, 4 Sep 2007, Steffen Klassert wrote:

quoted

On Tue, Sep 04, 2007 at 03:45:55AM +0530, Satyam Sharma wrote:

quoted

drivers/net/3c59x.c: In function 'vortex_up':
drivers/net/3c59x.c:1495: warning: 'err' may be used uninitialized in this function

This came in with the recently applied 3c59x-check-return-of-pci_enable_device patch
from Mark Hindley. I just compiled it on a PCI only machine so far, therefore I did
not notice the warning yet.

Hmm, the .config I built with had PCI=y as well. Probably a compiler
version difference -- Jeff also mentioned yesterday that some newer
GCC versions fail to warn about uninitialized variables cases.

Sorry, this is my bad. I have just checked: there is no warning with gcc
4.2 or 4.1, but 3.3 emits the warning. 

This is a GCC bug (regression, actually, as you've found out) -- no two
ways about it. Although different from the kind Jeff mentioned couple days
back -- that was about wising GCC up to false positives and /not/ emitting
warnings. But here a genuine problem was not complained about, so this is
more serious. Do you plan to open up a bug at gcc.gnu.org/bugzilla/ ?


Satyam