kbuild: Add -Wa,--fatal-warnings to as-instr invocation

commit 0ee695a471a750cad4fff22286d91e038b1ef62f upstream.

Certain assembler instruction tests may only induce warnings from the
assembler on

kbuild: Add -Wa,--fatal-warnings to as-instr invocation

commit 0ee695a471a750cad4fff22286d91e038b1ef62f upstream.

Certain assembler instruction tests may only induce warnings from the
assembler on an unsupported instruction or option, which causes as-instr
to succeed when it was expected to fail. Some tests workaround this
limitation by additionally testing that invalid input fails as expected.
However, this is fragile if the assembler is changed to accept the
invalid input, as it will cause the instruction/option to be unavailable
like it was unsupported even when it is.

Use '-Wa,--fatal-warnings' in the as-instr macro to turn these warnings
into hard errors, which avoids this fragility and makes tests more
robust and well formed.

Cc: stable@vger.kernel.org
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Tested-by: Andy Chiu <andybnac@gmail.com>
Reviewed-by: Andy Chiu <andybnac@gmail.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20240125-fix-riscv-option-arch-llvm-18-v1-1-390ac9cc3cd0@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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powerpc: remove checks for binutils older than 2.25

Commit e4412739472b ("Documentation: raise minimum supported version of
binutils to 2.25") allows us to remove the checks for old binutils.

There

powerpc: remove checks for binutils older than 2.25

Commit e4412739472b ("Documentation: raise minimum supported version of
binutils to 2.25") allows us to remove the checks for old binutils.

There is no more user for ld-ifversion. Remove it as well.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230119082250.151485-1-masahiroy@kernel.org

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kbuild: Add KBUILD_CPPFLAGS to as-option invocation

After commit feb843a469fb ("kbuild: add $(CLANG_FLAGS) to
KBUILD_CPPFLAGS"), there is an error while building certain PowerPC
assembly files with

kbuild: Add KBUILD_CPPFLAGS to as-option invocation

After commit feb843a469fb ("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 d5c8d6e0fa61 ("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: feb843a469fb ("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>

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kbuild: Add CLANG_FLAGS to as-instr

A future change will move CLANG_FLAGS from KBUILD_{A,C}FLAGS to
KBUILD_CPPFLAGS so that '--target' is available while preprocessing.
When that occurs, the followi

kbuild: Add CLANG_FLAGS to as-instr

A future change will move CLANG_FLAGS from KBUILD_{A,C}FLAGS to
KBUILD_CPPFLAGS so that '--target' is available while preprocessing.
When that occurs, the following errors appear multiple times when
building ARCH=powerpc powernv_defconfig:

ld.lld: error: vmlinux.a(arch/powerpc/kernel/head_64.o):(.text+0x12d4): relocation R_PPC64_ADDR16_HI out of range: -4611686018409717520 is not in [-2147483648, 2147483647]; references '__start___soft_mask_table'
ld.lld: error: vmlinux.a(arch/powerpc/kernel/head_64.o):(.text+0x12e8): relocation R_PPC64_ADDR16_HI out of range: -4611686018409717392 is not in [-2147483648, 2147483647]; references '__stop___soft_mask_table'

Diffing the .o.cmd files reveals that -DHAVE_AS_ATHIGH=1 is not present
anymore, because as-instr only uses KBUILD_AFLAGS, which will no longer
contain '--target'.

Mirror Kconfig's as-instr and add CLANG_FLAGS explicitly to the
invocation to ensure the target information is always present.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

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kbuild: Update assembler calls to use proper flags and language target

as-instr uses KBUILD_AFLAGS, but as-option uses KBUILD_CFLAGS. This can
cause as-option to fail unexpectedly when CONFIG_WERROR

kbuild: Update assembler calls to use proper flags and language target

as-instr uses KBUILD_AFLAGS, but as-option uses KBUILD_CFLAGS. This can
cause as-option to fail unexpectedly when CONFIG_WERROR is set, because
clang will emit -Werror,-Wunused-command-line-argument for various -m
and -f flags in KBUILD_CFLAGS for assembler sources.

Callers of as-option and as-instr should be adding flags to
KBUILD_AFLAGS / aflags-y, not KBUILD_CFLAGS / cflags-y. Use
KBUILD_AFLAGS in all macros to clear up the initial problem.

Unfortunately, -Wunused-command-line-argument can still be triggered
with clang by the presence of warning flags or macro definitions because
'-x assembler' is used, instead of '-x assembler-with-cpp', which will
consume these flags. Switch to '-x assembler-with-cpp' in places where
'-x assembler' is used, as the compiler is always used as the driver for
out of line assembler sources in the kernel.

Finally, add -Werror to these macros so that they behave consistently
whether or not CONFIG_WERROR is set.

[nathan: Reworded and expanded on problems in commit message
Use '-x assembler-with-cpp' in a couple more places]

Link: https://github.com/ClangBuiltLinux/linux/issues/1699
Suggested-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

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kbuild: add test-{ge,gt,le,lt} macros

GNU Make 4.4 introduced $(intcmp ...), which is useful to compare two
integers without forking a new process.

Add test-{ge,gt,le,lt} macros, which work more ef

kbuild: add test-{ge,gt,le,lt} macros

GNU Make 4.4 introduced $(intcmp ...), which is useful to compare two
integers without forking a new process.

Add test-{ge,gt,le,lt} macros, which work more efficiently with GNU
Make >= 4.4. For older Make versions, they fall back to the 'test'
shell command.

The first two parameters to $(intcmp ...) must not be empty. To avoid
the syntax error, I appended '0' to them. Fortunately, '00' is treated
as '0'. This is needed because CONFIG options may expand to an empty
string when the kernel configuration is not included.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com> # RISC-V
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

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Makefile.compiler: replace cc-ifversion with compiler-specific macros

cc-ifversion is GCC specific. Replace it with compiler specific
variants. Update the users of cc-ifversion to use these new macr

Makefile.compiler: replace cc-ifversion with compiler-specific macros

cc-ifversion is GCC specific. Replace it with compiler specific
variants. Update the users of cc-ifversion to use these new macros.

Link: https://github.com/ClangBuiltLinux/linux/issues/350
Link: https://lore.kernel.org/llvm/CAGG=3QWSAUakO42kubrCap8fp-gm1ERJJAYXTnP1iHk_wrH=BQ@mail.gmail.com/
Suggested-by: Bill Wendling <morbo@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

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kbuild: set EXIT trap before creating temporary directory

Swap the order of 'mkdir' and 'trap' just in case the subshell is
interrupted between 'mkdir' and 'trap' although the effect might be
subtle

kbuild: set EXIT trap before creating temporary directory

Swap the order of 'mkdir' and 'trap' just in case the subshell is
interrupted between 'mkdir' and 'trap' although the effect might be
subtle.

This does not intend to make the cleanup perfect. There are more cases
that miss to remove the tmp directory, for example:

- When interrupted, dash does not invoke the EXIT trap (bash does)

- 'rm' command might be interrupted before removing the directory

I am not addressing all the cases since the tmp directory is harmless
after all.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

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kbuild: remove TMPO from try-run

TMPO is only used by arch/x86/Makefile.

Change arch/x86/Makefile to use $$TMPO.o and remove TMPO from
scripts/Makefile.compiler.

Signed-off-by: Masahiro Yamada <ma

kbuild: remove TMPO from try-run

TMPO is only used by arch/x86/Makefile.

Change arch/x86/Makefile to use $$TMPO.o and remove TMPO from
scripts/Makefile.compiler.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

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kbuild: split cc-option and friends to scripts/Makefile.compiler

scripts/Kbuild.include is included everywhere, but macros such as
cc-option are needed by build targets only.

For example, when 'mak

kbuild: split cc-option and friends to scripts/Makefile.compiler

scripts/Kbuild.include is included everywhere, but macros such as
cc-option are needed by build targets only.

For example, when 'make clean' traverses the tree, it does not need
to evaluate $(call cc-option,).

Split cc-option, ld-option, etc. to scripts/Makefile.compiler, which
is only included from the top Makefile and scripts/Makefile.build.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

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