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a708376361
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: 25cd5a3914 ("ARM: tegra: Add speedo-based process identification")
Link: https://github.com/ClangBuiltLinux/linux/issues/1488
Suggested-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.