• Nathan Chancellor's avatar
    soc/tegra: fuse: Fix bitwise vs. logical OR warning · a7083763
    Nathan Chancellor authored
    A new warning in clang points out two instances where boolean
    expressions are being used with a bitwise OR instead of logical OR:
    
    drivers/soc/tegra/fuse/speedo-tegra20.c:72:9: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical]
                    reg = tegra_fuse_read_spare(i) |
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~
                                                   ||
    drivers/soc/tegra/fuse/speedo-tegra20.c:72:9: note: cast one or both operands to int to silence this warning
    drivers/soc/tegra/fuse/speedo-tegra20.c:87:9: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical]
                    reg = tegra_fuse_read_spare(i) |
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~
                                                   ||
    drivers/soc/tegra/fuse/speedo-tegra20.c:87:9: note: cast one or both operands to int to silence this warning
    2 warnings generated.
    
    The motivation for the warning is that logical operations short circuit
    while bitwise operations do not.
    
    In this instance, tegra_fuse_read_spare() is not semantically returning
    a boolean, it is returning a bit value. Use u32 for its return type so
    that it can be used with either bitwise or boolean operators without any
    warnings.
    
    Fixes: 25cd5a39 ("ARM: tegra: Add speedo-based process identification")
    Link: https://github.com/ClangBuiltLinux/linux/issues/1488Suggested-by: default avatarMichał Mirosław <mirq-linux@rere.qmqm.pl>
    Signed-off-by: default avatarNathan Chancellor <nathan@kernel.org>
    Reviewed-by: default avatarNick Desaulniers <ndesaulniers@google.com>
    Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
    a7083763
fuse-tegra.c 12.8 KB