• Arnd Bergmann's avatar
    net/mlx5e: Fix a -Wmaybe-uninitialized warning · abeffce9
    Arnd Bergmann authored
    As found by Olof's build bot, we gain a harmless warning about a
    potential uninitialized variable reference in mlx5:
    
    drivers/net/ethernet/mellanox/mlx5/core/en_tc.c: In function 'parse_tc_fdb_actions':
    drivers/net/ethernet/mellanox/mlx5/core/en_tc.c:769:13: warning: 'out_dev' may be used uninitialized in this function [-Wmaybe-uninitialized]
    drivers/net/ethernet/mellanox/mlx5/core/en_tc.c:811:21: note: 'out_dev' was declared here
    
    This was introduced through the addition of an 'IS_ERR/PTR_ERR' pair
    that gcc is unfortunately unable to completely figure out.
    
    The problem being gcc cannot tell that if(IS_ERR()) in
    mlx5e_route_lookup_ipv4() is equivalent to checking if(err) later,
    so it assumes that 'out_dev' is used after the 'return PTR_ERR(rt)'.
    
    The PTR_ERR_OR_ZERO() case by comparison is fairly easy to detect
    by gcc, so it can't get that wrong, so it no longer warns.
    
    Hadar Hen Zion already attempted to fix the warning earlier by adding fake
    initializations, but that ended up not fully addressing all warnings, so
    I'm reverting it now that it is no longer needed.
    
    Link: http://arm-soc.lixom.net/buildlogs/mainline/v4.10-rc3-98-gcff3b2c/
    Fixes: a42485eb ("net/mlx5e: TC ipv4 tunnel encap offload error flow fixes")
    Fixes: a757d108
    
     ("net/mlx5e: Fix kbuild warnings for uninitialized parameters")
    Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
    Signed-off-by: default avatarOr Gerlitz <ogerlitz@mellanox.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    abeffce9
en_tc.c 30.6 KB