Clang does not support this option and errors out:
clang-11: error: unknown argument: '-mexplicit-relocs'
Clang does not appear to need this flag like GCC does because the jalr
check that was added in commit 976c23af3e ("mips: vdso: add build
time check that no 'jalr t9' calls left") passes just fine with
$ make ARCH=mips CC=clang CROSS_COMPILE=mipsel-linux-gnu- malta_defconfig arch/mips/vdso/
even before commit d3f703c435 ("mips: vdso: fix 'jalr t9' crash in
vdso code").
-mrelax-pic-calls has been supported since clang 9, which is the
earliest version that could build a working MIPS kernel, and it is the
default for clang so just leave it be.
Fixes: d3f703c435 ("mips: vdso: fix 'jalr t9' crash in vdso code")
Link: https://github.com/ClangBuiltLinux/linux/issues/890
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
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