25 Apr, 2021
1 commit
-
The kernel build uses various tools, many of which are provided by the
same software suite, for example, LLVM and Binutils.When you raise the minimum version of Clang/LLVM, you need to update
clang_min_version in scripts/cc-version.sh and also lld_min_version in
scripts/ld-version.sh.Kbuild can handle CC=clang and LD=ld.lld independently, but it does not
make much sense to maintain their versions separately.Let's create a central place of minimum tool versions so you do not need
to touch multiple files. scripts/min-tool-version.sh prints the minimum
version of the given tool.Signed-off-by: Masahiro Yamada
Reviewed-by: Nathan Chancellor
Acked-by: Miguel Ojeda
Tested-by: Sedat Dilek
16 Feb, 2021
1 commit
-
Paul Gortmaker reported a regression in the GCC version check. [1]
If you use GCC 4.8, the build breaks before showing the error message
"error Sorry, your version of GCC is too old - please use 4.9 or newer."I do not want to apply his fix-up since it implies we would not be able
to remove any cc-option test. Anyway, I admit checking the GCC version
in is too late.Almost at the same time, Linus also suggested to move the compiler
version error to Kconfig time. [2]I unified the two similar scripts, gcc-version.sh and clang-version.sh
into cc-version.sh. The old scripts invoked the compiler multiple times
(3 times for gcc-version.sh, 4 times for clang-version.sh). I refactored
the code so the new one invokes the compiler just once, and also tried
my best to use shell-builtin commands where possible.The new script runs faster.
$ time ./scripts/clang-version.sh clang
120000real 0m0.029s
user 0m0.012s
sys 0m0.021s$ time ./scripts/cc-version.sh clang
Clang 120000real 0m0.009s
user 0m0.006s
sys 0m0.004scc-version.sh also shows an error message if the compiler is too old:
$ make defconfig CC=clang-9
*** Default configuration is based on 'x86_64_defconfig'
***
*** Compiler is too old.
*** Your Clang version: 9.0.1
*** Minimum Clang version: 10.0.1
***
scripts/Kconfig.include:46: Sorry, this compiler is not supported.
make[1]: *** [scripts/kconfig/Makefile:81: defconfig] Error 1
make: *** [Makefile:602: defconfig] Error 2The new script takes care of ICC because we have
although I am not sure if building the kernel with ICC is well-supported.[1]: https://lore.kernel.org/r/20210110190807.134996-1-paul.gortmaker@windriver.com
[2]: https://lore.kernel.org/r/CAHk-=wh-+TMHPTFo1qs-MYyK7tZh-OQovA=pP3=e06aCVp6_kA@mail.gmail.comFixes: 87de84c9140e ("kbuild: remove cc-option test of -Werror=date-time")
Reported-by: Paul Gortmaker
Suggested-by: Linus Torvalds
Reviewed-by: Nick Desaulniers
Tested-by: Nick Desaulniers
Reviewed-by: Nathan Chancellor
Tested-by: Nathan Chancellor
Reviewed-by: Miguel Ojeda
Tested-by: Miguel Ojeda
Tested-by: Sedat Dilek
Signed-off-by: Masahiro Yamada