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.
Nathan Chancellor
authored
After commit feb843a4 ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS"), there is an error while building certain PowerPC assembly files with clang: arch/powerpc/lib/copypage_power7.S: Assembler messages: arch/powerpc/lib/copypage_power7.S:34: Error: junk at end of line: `0b01000' arch/powerpc/lib/copypage_power7.S:35: Error: junk at end of line: `0b01010' arch/powerpc/lib/copypage_power7.S:37: Error: junk at end of line: `0b01000' arch/powerpc/lib/copypage_power7.S:38: Error: junk at end of line: `0b01010' arch/powerpc/lib/copypage_power7.S:40: Error: junk at end of line: `0b01010' clang: error: assembler command failed with exit code 1 (use -v to see invocation) as-option only uses KBUILD_AFLAGS, so after removing CLANG_FLAGS from KBUILD_AFLAGS, there is no more '--target=' or '--prefix=' flags. As a result of those missing flags, the host target will be tested during as-option calls and likely fail, meaning necessary flags may not get added when building assembly files, resulting in errors like seen above. Add KBUILD_CPPFLAGS to as-option invocations to clear up the errors. This should have been done in commit d5c8d6e0 ("kbuild: Update assembler calls to use proper flags and language target"), which switched from using the assembler target to the assembler-with-cpp target, so flags that affect preprocessing are passed along in all relevant tests. as-option now mirrors cc-option. Fixes: feb843a4 ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS") Reported-by:Linux Kernel Functional Testing <lkft@linaro.org> Closes: https://lore.kernel.org/CA+G9fYs=koW9WardsTtora+nMgLR3raHz-LSLr58tgX4T5Mxag@mail.gmail.com/ Signed-off-by:
Nathan Chancellor <nathan@kernel.org> Tested-by:
Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by:
Masahiro Yamada <masahiroy@kernel.org>