linux-yocto/rust/Makefile
Miguel Ojeda f135c9dd62 rust: workaround rustdoc target modifiers bug
commit abbf9a44944171ca99c150adad9361a2f517d3b6 upstream.

Starting with Rust 1.88.0 (released 2025-06-26), `rustdoc` complains
about a target modifier mismatch in configurations where `-Zfixed-x18`
is passed:

    error: mixing `-Zfixed-x18` will cause an ABI mismatch in crate `rust_out`
      |
      = help: the `-Zfixed-x18` flag modifies the ABI so Rust crates compiled with different values of this flag cannot be used together safely
      = note: unset `-Zfixed-x18` in this crate is incompatible with `-Zfixed-x18=` in dependency `core`
      = help: set `-Zfixed-x18=` in this crate or unset `-Zfixed-x18` in `core`
      = help: if you are sure this will not cause problems, you may use `-Cunsafe-allow-abi-mismatch=fixed-x18` to silence this error

The reason is that `rustdoc` was not passing the target modifiers when
configuring the session options, and thus it would report a mismatch
that did not exist as soon as a target modifier is used in a dependency.

We did not notice it in the kernel until now because `-Zfixed-x18` has
been a target modifier only since 1.88.0 (and it is the only one we use
so far).

The issue has been reported upstream [1] and a fix has been submitted
[2], including a test similar to the kernel case.

  [ This is now fixed upstream (thanks Guillaume for the quick review),
    so it will be fixed in Rust 1.90.0 (expected 2025-09-18).

      - Miguel ]

Meanwhile, conditionally pass `-Cunsafe-allow-abi-mismatch=fixed-x18`
to workaround the issue on our side.

Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Reported-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Closes: https://lore.kernel.org/rust-for-linux/36cdc798-524f-4910-8b77-d7b9fac08d77@oss.qualcomm.com/
Link: https://github.com/rust-lang/rust/issues/144521 [1]
Link: https://github.com/rust-lang/rust/pull/144523 [2]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250727092317.2930617-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-08-20 18:41:35 +02:00

24 KiB

SPDX-License-Identifier: GPL-2.0

Where to place rustdoc generated documentation

rustdoc_output := $(objtree)/Documentation/output/rust/rustdoc

obj-$(CONFIG_RUST) += core.o compiler_builtins.o ffi.o always-$(CONFIG_RUST) += exports_core_generated.h

Missing prototypes are expected in the helpers since these are exported

for Rust only, thus there is no header nor prototypes.

obj-$(CONFIG_RUST) += helpers/helpers.o CFLAGS_REMOVE_helpers/helpers.o = -Wmissing-prototypes -Wmissing-declarations

always-$(CONFIG_RUST) += bindings/bindings_generated.rs bindings/bindings_helpers_generated.rs obj-$(CONFIG_RUST) += bindings.o pin_init.o kernel.o always-$(CONFIG_RUST) += exports_helpers_generated.h
exports_bindings_generated.h exports_kernel_generated.h

always-$(CONFIG_RUST) += uapi/uapi_generated.rs obj-$(CONFIG_RUST) += uapi.o

ifdef CONFIG_RUST_BUILD_ASSERT_ALLOW obj-$(CONFIG_RUST) += build_error.o else always-$(CONFIG_RUST) += build_error.o endif

obj-$(CONFIG_RUST) += exports.o

always-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated.rs always-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated_kunit.c

obj-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated.o obj-$(CONFIG_RUST_KERNEL_DOCTESTS) += doctests_kernel_generated_kunit.o

always-$(subst y,$(CONFIG_RUST),$(CONFIG_JUMP_LABEL)) += kernel/generated_arch_static_branch_asm.rs

Avoids running $(RUSTC) when it may not be available.

ifdef CONFIG_RUST

libmacros_name := $(shell MAKEFLAGS= $(RUSTC) --print file-names --crate-name macros --crate-type proc-macro - </dev/null) libmacros_extension := $(patsubst libmacros.%,%,$(libmacros_name))

libpin_init_internal_name := $(shell MAKEFLAGS= $(RUSTC) --print file-names --crate-name pin_init_internal --crate-type proc-macro - </dev/null) libpin_init_internal_extension := $(patsubst libpin_init_internal.%,%,$(libpin_init_internal_name))

always-$(CONFIG_RUST) += $(libmacros_name) $(libpin_init_internal_name)

$(rust_flags) is passed in case the user added --sysroot.

rustc_sysroot := $(shell MAKEFLAGS= $(RUSTC) $(rust_flags) --print sysroot) rustc_host_target := $(shell $(RUSTC) --version --verbose | grep -F 'host: ' | cut -d' ' -f2) RUST_LIB_SRC ?= $(rustc_sysroot)/lib/rustlib/src/rust/library

ifneq ($(quiet),) rust_test_quiet=-q rustdoc_test_quiet=--test-args -q rustdoc_test_kernel_quiet=>/dev/null endif

core-cfgs =
--cfg no_fp_fmt_parse

core-edition := $(if $(call rustc-min-version,108700),2024,2021)

rustdoc did not save the target modifiers, thus workaround for

the time being (https://github.com/rust-lang/rust/issues/144521).

rustdoc_modifiers_workaround := $(if $(call rustc-min-version,108800),-Cunsafe-allow-abi-mismatch=fixed-x18)

rustc recognizes --remap-path-prefix since 1.26.0, but rustdoc only

since Rust 1.81.0. Moreover, rustdoc ICEs on out-of-tree builds since Rust

1.82.0 (https://github.com/rust-lang/rust/issues/138520). Thus workaround both

issues skipping the flag. The former also applies to RUSTDOC TK.

quiet_cmd_rustdoc = RUSTDOC $(if $(rustdoc_host),H, ) $< cmd_rustdoc =
OBJTREE=$(abspath $(objtree))
$(RUSTDOC) $(filter-out $(skip_flags) --remap-path-prefix=%,$(if $(rustdoc_host),$(rust_common_flags),$(rust_flags)))
$(rustc_target_flags) -L$(objtree)/$(obj)
-Zunstable-options --generate-link-to-definition
--output $(rustdoc_output)
--crate-name $(subst rustdoc-,,$@)
$(rustdoc_modifiers_workaround)
$(if $(rustdoc_host),,--sysroot=/dev/null)
@$(objtree)/include/generated/rustc_cfg $<

The html_logo_url and html_favicon_url forms of the doc attribute

can be used to specify a custom logo. However:

- The given value is used as-is, thus it cannot be relative or a local file

(unlike the non-custom case) since the generated docs have subfolders.

- It requires adding it to every crate.

- It requires changing core which comes from the sysroot.

Using -Zcrate-attr would solve the last two points, but not the first.

The https://github.com/rust-lang/rfcs/pull/3226 RFC suggests two new

command-like flags to solve the issue. Meanwhile, we use the non-custom case

and then retouch the generated files.

rustdoc: rustdoc-core rustdoc-macros rustdoc-compiler_builtins
rustdoc-kernel rustdoc-pin_init $(Q)cp $(srctree)/Documentation/images/logo.svg $(rustdoc_output)/static.files/ $(Q)cp $(srctree)/Documentation/images/COPYING-logo $(rustdoc_output)/static.files/ $(Q)find $(rustdoc_output) -name '.html' -type f -print0 | xargs -0 sed -Ei
-e 's:rust-logo-[0-9a-f]+.svg:logo.svg:g'
-e 's:favicon-[0-9a-f]+.svg:logo.svg:g'
-e 's:::g'
-e 's:<a href="srctree/([^"]+)">::g' $(Q)for f in $(rustdoc_output)/static.files/rustdoc-
.css; do
echo ".logo-container > img { object-fit: contain; }" >> $$f; done

rustdoc-macros: private rustdoc_host = yes rustdoc-macros: private rustc_target_flags = --crate-type proc-macro
--extern proc_macro rustdoc-macros: $(src)/macros/lib.rs rustdoc-clean FORCE +$(call if_changed,rustdoc)

Starting with Rust 1.82.0, skipping -Wrustdoc::unescaped_backticks should

not be needed -- see https://github.com/rust-lang/rust/pull/128307.

rustdoc-core: private skip_flags = --edition=2021 -Wrustdoc::unescaped_backticks rustdoc-core: private rustc_target_flags = --edition=$(core-edition) $(core-cfgs) rustdoc-core: $(RUST_LIB_SRC)/core/src/lib.rs rustdoc-clean FORCE +$(call if_changed,rustdoc)

rustdoc-compiler_builtins: $(src)/compiler_builtins.rs rustdoc-core FORCE +$(call if_changed,rustdoc)

rustdoc-ffi: $(src)/ffi.rs rustdoc-core FORCE +$(call if_changed,rustdoc)

rustdoc-pin_init_internal: private rustdoc_host = yes rustdoc-pin_init_internal: private rustc_target_flags = --cfg kernel
--extern proc_macro --crate-type proc-macro rustdoc-pin_init_internal: $(src)/pin-init/internal/src/lib.rs
rustdoc-clean FORCE +$(call if_changed,rustdoc)

rustdoc-pin_init: private rustdoc_host = yes rustdoc-pin_init: private rustc_target_flags = --extern pin_init_internal
--extern macros --extern alloc --cfg kernel --cfg feature="alloc" rustdoc-pin_init: $(src)/pin-init/src/lib.rs rustdoc-pin_init_internal
rustdoc-macros FORCE +$(call if_changed,rustdoc)

rustdoc-kernel: private rustc_target_flags = --extern ffi --extern pin_init
--extern build_error --extern macros
--extern bindings --extern uapi rustdoc-kernel: $(src)/kernel/lib.rs rustdoc-core rustdoc-ffi rustdoc-macros
rustdoc-pin_init rustdoc-compiler_builtins $(obj)/$(libmacros_name)
$(obj)/bindings.o FORCE +$(call if_changed,rustdoc)

rustdoc-clean: FORCE $(Q)rm -rf $(rustdoc_output)

quiet_cmd_rustc_test_library = $(RUSTC_OR_CLIPPY_QUIET) TL $< cmd_rustc_test_library =
OBJTREE=$(abspath $(objtree))
$(RUSTC_OR_CLIPPY) $(rust_common_flags)
@$(objtree)/include/generated/rustc_cfg $(rustc_target_flags)
--crate-type $(if $(rustc_test_library_proc),proc-macro,rlib)
--out-dir $(objtree)/$(obj)/test --cfg testlib
-L$(objtree)/$(obj)/test
--crate-name $(subst rusttest-,,$(subst rusttestlib-,,$@)) $<

rusttestlib-build_error: $(src)/build_error.rs FORCE +$(call if_changed,rustc_test_library)

rusttestlib-ffi: $(src)/ffi.rs FORCE +$(call if_changed,rustc_test_library)

rusttestlib-macros: private rustc_target_flags = --extern proc_macro rusttestlib-macros: private rustc_test_library_proc = yes rusttestlib-macros: $(src)/macros/lib.rs FORCE +$(call if_changed,rustc_test_library)

rusttestlib-pin_init_internal: private rustc_target_flags = --cfg kernel
--extern proc_macro rusttestlib-pin_init_internal: private rustc_test_library_proc = yes rusttestlib-pin_init_internal: $(src)/pin-init/internal/src/lib.rs FORCE +$(call if_changed,rustc_test_library)

rusttestlib-pin_init: private rustc_target_flags = --extern pin_init_internal
--extern macros --cfg kernel rusttestlib-pin_init: $(src)/pin-init/src/lib.rs rusttestlib-macros
rusttestlib-pin_init_internal $(obj)/$(libpin_init_internal_name) FORCE +$(call if_changed,rustc_test_library)

rusttestlib-kernel: private rustc_target_flags = --extern ffi
--extern build_error --extern macros --extern pin_init
--extern bindings --extern uapi rusttestlib-kernel: $(src)/kernel/lib.rs rusttestlib-bindings rusttestlib-uapi
rusttestlib-build_error rusttestlib-pin_init $(obj)/$(libmacros_name)
$(obj)/bindings.o FORCE +$(call if_changed,rustc_test_library)

rusttestlib-bindings: private rustc_target_flags = --extern ffi rusttestlib-bindings: $(src)/bindings/lib.rs rusttestlib-ffi FORCE +$(call if_changed,rustc_test_library)

rusttestlib-uapi: private rustc_target_flags = --extern ffi rusttestlib-uapi: $(src)/uapi/lib.rs rusttestlib-ffi FORCE +$(call if_changed,rustc_test_library)

quiet_cmd_rustdoc_test = RUSTDOC T $< cmd_rustdoc_test =
RUST_MODFILE=test.rs
OBJTREE=$(abspath $(objtree))
$(RUSTDOC) --test $(rust_common_flags)
-Zcrate-attr='feature(used_with_arg)'
@$(objtree)/include/generated/rustc_cfg
$(rustc_target_flags) $(rustdoc_test_target_flags)
$(rustdoc_test_quiet)
-L$(objtree)/$(obj)/test --output $(rustdoc_output)
--crate-name $(subst rusttest-,,$@) $<

quiet_cmd_rustdoc_test_kernel = RUSTDOC TK $< cmd_rustdoc_test_kernel =
rm -rf $(objtree)/$(obj)/test/doctests/kernel;
mkdir -p $(objtree)/$(obj)/test/doctests/kernel;
OBJTREE=$(abspath $(objtree))
$(RUSTDOC) --test $(filter-out --remap-path-prefix=%,$(rust_flags))
-L$(objtree)/$(obj) --extern ffi --extern pin_init
--extern kernel --extern build_error --extern macros
--extern bindings --extern uapi
--no-run --crate-name kernel -Zunstable-options
--sysroot=/dev/null
$(rustdoc_modifiers_workaround)
--test-builder $(objtree)/scripts/rustdoc_test_builder
$< $(rustdoc_test_kernel_quiet);
$(objtree)/scripts/rustdoc_test_gen

%/doctests_kernel_generated.rs %/doctests_kernel_generated_kunit.c:
$(src)/kernel/lib.rs $(obj)/kernel.o
$(objtree)/scripts/rustdoc_test_builder
$(objtree)/scripts/rustdoc_test_gen FORCE +$(call if_changed,rustdoc_test_kernel)

We cannot use -Zpanic-abort-tests because some tests are dynamic,

so for the moment we skip -Cpanic=abort.

quiet_cmd_rustc_test = $(RUSTC_OR_CLIPPY_QUIET) T $< cmd_rustc_test =
OBJTREE=$(abspath $(objtree))
$(RUSTC_OR_CLIPPY) --test $(rust_common_flags)
@$(objtree)/include/generated/rustc_cfg
$(rustc_target_flags) --out-dir $(objtree)/$(obj)/test
-L$(objtree)/$(obj)/test
--crate-name $(subst rusttest-,,$@) $<;
$(objtree)/$(obj)/test/$(subst rusttest-,,$@) $(rust_test_quiet)
$(rustc_test_run_flags)

rusttest: rusttest-macros rusttest-kernel

rusttest-macros: private rustc_target_flags = --extern proc_macro
--extern macros --extern kernel --extern pin_init rusttest-macros: private rustdoc_test_target_flags = --crate-type proc-macro rusttest-macros: $(src)/macros/lib.rs
rusttestlib-macros rusttestlib-kernel rusttestlib-pin_init FORCE +$(call if_changed,rustc_test) +$(call if_changed,rustdoc_test)

rusttest-kernel: private rustc_target_flags = --extern ffi --extern pin_init
--extern build_error --extern macros --extern bindings --extern uapi rusttest-kernel: $(src)/kernel/lib.rs rusttestlib-ffi rusttestlib-kernel
rusttestlib-build_error rusttestlib-macros rusttestlib-bindings
rusttestlib-uapi rusttestlib-pin_init FORCE +$(call if_changed,rustc_test)

ifdef CONFIG_CC_IS_CLANG bindgen_c_flags = $(c_flags) else

bindgen relies on libclang to parse C. Ideally, bindgen would support a GCC

plugin backend and/or the Clang driver would be perfectly compatible with GCC.

For the moment, here we are tweaking the flags on the fly. This is a hack,

and some kernel configurations may not work (e.g. GCC_PLUGIN_RANDSTRUCT

if we end up using one of those structs).

bindgen_skip_c_flags := -mno-fp-ret-in-387 -mpreferred-stack-boundary=%
-mskip-rax-setup -mgeneral-regs-only -msign-return-address=%
-mindirect-branch=thunk-extern -mindirect-branch-register
-mfunction-return=thunk-extern -mrecord-mcount -mabi=lp64
-mindirect-branch-cs-prefix -mstack-protector-guard% -mtraceback=no
-mno-pointers-to-nested-functions -mno-string
-mno-strict-align -mstrict-align -mdirect-extern-access
-mexplicit-relocs -mno-check-zero-division
-fconserve-stack -falign-jumps=% -falign-loops=%
-femit-struct-debug-baseonly -fno-ipa-cp-clone -fno-ipa-sra
-fno-partial-inlining -fplugin-arg-arm_ssp_per_task_plugin-%
-fno-reorder-blocks -fno-allow-store-data-races -fasan-shadow-offset=%
-fzero-call-used-regs=% -fno-stack-clash-protection
-fno-inline-functions-called-once -fsanitize=bounds-strict
-fstrict-flex-arrays=% -fmin-function-alignment=%
-fzero-init-padding-bits=% -mno-fdpic
--param=% --param asan-%

Derived from scripts/Makefile.clang.

BINDGEN_TARGET_x86 := x86_64-linux-gnu BINDGEN_TARGET_arm64 := aarch64-linux-gnu BINDGEN_TARGET_arm := arm-linux-gnueabi BINDGEN_TARGET_loongarch := loongarch64-linux-gnusf BINDGEN_TARGET_um := $(BINDGEN_TARGET_$(SUBARCH)) BINDGEN_TARGET := $(BINDGEN_TARGET_$(SRCARCH))

All warnings are inhibited since GCC builds are very experimental,

many GCC warnings are not supported by Clang, they may only appear in

some configurations, with new GCC versions, etc.

bindgen_extra_c_flags = -w --target=$(BINDGEN_TARGET)

Auto variable zero-initialization requires an additional special option with

clang that is going to be removed sometime in the future (likely in

clang-18), so make sure to pass this option only if clang supports it

(libclang major version < 16).

https://github.com/llvm/llvm-project/issues/44842

https://github.com/llvm/llvm-project/blob/llvmorg-16.0.0-rc2/clang/docs/ReleaseNotes.rst#deprecated-compiler-flags

ifdef CONFIG_INIT_STACK_ALL_ZERO libclang_maj_ver=$(shell $(BINDGEN) $(srctree)/scripts/rust_is_available_bindgen_libclang.h 2>&1 | sed -ne 's/.clang version [0-9]*./\1/p') ifeq ($(shell expr $(libclang_maj_ver) < 16), 1) bindgen_extra_c_flags += -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang endif endif

bindgen_c_flags = $(filter-out $(bindgen_skip_c_flags), $(c_flags))
$(bindgen_extra_c_flags) endif

ifdef CONFIG_LTO bindgen_c_flags_lto = $(filter-out $(CC_FLAGS_LTO), $(bindgen_c_flags)) else bindgen_c_flags_lto = $(bindgen_c_flags) endif

-fno-builtin is passed to avoid bindgen from using clang builtin

prototypes for functions like memcpy -- if this flag is not passed,

bindgen-generated prototypes use c_ulong or c_uint depending on

architecture instead of generating usize.

bindgen_c_flags_final = $(bindgen_c_flags_lto) -fno-builtin -D__BINDGEN__

Each bindgen release may upgrade the list of Rust target versions. By

default, the highest stable release in their list is used. Thus we need to set

a --rust-target to avoid future bindgen releases emitting code that

rustc may not understand. On top of that, bindgen does not support passing

an unknown Rust target version.

Therefore, the Rust target for bindgen can be only as high as the minimum

Rust version the kernel supports and only as high as the greatest stable Rust

target supported by the minimum bindgen version the kernel supports (that

is, if we do not test the actual rustc/bindgen versions running).

Starting with bindgen 0.71.0, we will be able to set any future Rust version

instead, i.e. we will be able to set here our minimum supported Rust version.

quiet_cmd_bindgen = BINDGEN $@ cmd_bindgen =
$(BINDGEN) $< $(bindgen_target_flags) --rust-target 1.68
--use-core --with-derive-default --ctypes-prefix ffi --no-layout-tests
--no-debug '.*' --enable-function-attribute-detection
-o $@ -- $(bindgen_c_flags_final) -DMODULE
$(bindgen_target_cflags) $(bindgen_target_extra)

$(obj)/bindings/bindings_generated.rs: private bindgen_target_flags =
$(shell grep -Ev '^#|^$$' $(src)/bindgen_parameters) $(obj)/bindings/bindings_generated.rs: private bindgen_target_extra = ;
sed -Ei 's/pub const RUST_CONST_HELPER_([a-zA-Z0-9_]*)/pub const \1/g' $@ $(obj)/bindings/bindings_generated.rs: $(src)/bindings/bindings_helper.h
$(src)/bindgen_parameters FORCE $(call if_changed_dep,bindgen)

$(obj)/uapi/uapi_generated.rs: private bindgen_target_flags =
$(shell grep -Ev '^#|^$$' $(src)/bindgen_parameters) $(obj)/uapi/uapi_generated.rs: $(src)/uapi/uapi_helper.h
$(src)/bindgen_parameters FORCE $(call if_changed_dep,bindgen)

See CFLAGS_REMOVE_helpers.o above. In addition, Clang on C does not warn

with -Wmissing-declarations (unlike GCC), so it is not strictly needed here

given it is libclang; but for consistency, future Clang changes and/or

a potential future GCC backend for bindgen, we disable it too.

$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_flags =
--blocklist-type '.' --allowlist-var ''
--allowlist-function 'rust_helper_.
' $(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_cflags =
-I$(objtree)/$(obj) -Wno-missing-prototypes -Wno-missing-declarations $(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_extra = ;
sed -Ei 's/pub fn rust_helper_([a-zA-Z0-9_]*)/#[link_name="rust_helper_\1"]\n pub fn \1/g' $@ $(obj)/bindings/bindings_helpers_generated.rs: $(src)/helpers/helpers.c FORCE $(call if_changed_dep,bindgen)

rust_exports = $(NM) -p --defined-only $(1) | awk '$$2~/(T|R|D|B)/ && $$3!~/__(pfx|cfi|odr_asan)/ { printf $(2),$$3 }'

quiet_cmd_exports = EXPORTS $@ cmd_exports =
$(call rust_exports,$<,"EXPORT_SYMBOL_RUST_GPL(%s);\n") > $@

$(obj)/exports_core_generated.h: $(obj)/core.o FORCE $(call if_changed,exports)

Even though Rust kernel modules should never use the bindings directly,

symbols from the bindings crate and the C helpers need to be exported

because Rust generics and inlined functions may not get their code generated

in the crate where they are defined. Other helpers, called from non-inline

functions, may not be exported, in principle. However, in general, the Rust

compiler does not guarantee codegen will be performed for a non-inline

function either. Therefore, we export all symbols from helpers and bindings.

In the future, this may be revisited to reduce the number of exports after

the compiler is informed about the places codegen is required.

$(obj)/exports_helpers_generated.h: $(obj)/helpers/helpers.o FORCE $(call if_changed,exports)

$(obj)/exports_bindings_generated.h: $(obj)/bindings.o FORCE $(call if_changed,exports)

$(obj)/exports_kernel_generated.h: $(obj)/kernel.o FORCE $(call if_changed,exports)

quiet_cmd_rustc_procmacro = $(RUSTC_OR_CLIPPY_QUIET) P $@ cmd_rustc_procmacro =
$(RUSTC_OR_CLIPPY) $(rust_common_flags) $(rustc_target_flags)
-Clinker-flavor=gcc -Clinker=$(HOSTCC)
-Clink-args='$(call escsq,$(KBUILD_PROCMACROLDFLAGS))'
--emit=dep-info=$(depfile) --emit=link=$@ --extern proc_macro
--crate-type proc-macro
--crate-name $(patsubst lib%.$(libmacros_extension),%,$(notdir $@))
@$(objtree)/include/generated/rustc_cfg $<

Procedural macros can only be used with the rustc that compiled it.

$(obj)/$(libmacros_name): $(src)/macros/lib.rs FORCE +$(call if_changed_dep,rustc_procmacro)

$(obj)/$(libpin_init_internal_name): private rustc_target_flags = --cfg kernel $(obj)/$(libpin_init_internal_name): $(src)/pin-init/internal/src/lib.rs FORCE +$(call if_changed_dep,rustc_procmacro)

quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L $@ cmd_rustc_library =
OBJTREE=$(abspath $(objtree))
$(if $(skip_clippy),$(RUSTC),$(RUSTC_OR_CLIPPY))
$(filter-out $(skip_flags),$(rust_flags)) $(rustc_target_flags)
--emit=dep-info=$(depfile) --emit=obj=$@
--emit=metadata=$(dir $@)$(patsubst %.o,lib%.rmeta,$(notdir $@))
--crate-type rlib -L$(objtree)/$(obj)
--crate-name $(patsubst %.o,%,$(notdir $@)) $<
--sysroot=/dev/null
$(if $(rustc_objcopy),;$(OBJCOPY) $(rustc_objcopy) $@)
$(cmd_objtool)

rust-analyzer: $(Q)MAKEFLAGS= $(srctree)/scripts/generate_rust_analyzer.py
--cfgs='core=$(core-cfgs)' $(core-edition)
$(realpath $(srctree)) $(realpath $(objtree))
$(rustc_sysroot) $(RUST_LIB_SRC) $(if $(KBUILD_EXTMOD),$(srcroot))
> rust-project.json

redirect-intrinsics =
__addsf3 __eqsf2 __extendsfdf2 __gesf2 __lesf2 __ltsf2 __mulsf3 __nesf2 __truncdfsf2 __unordsf2
__adddf3 __eqdf2 __ledf2 __ltdf2 __muldf3 __unorddf2
__muloti4 __multi3
__udivmodti4 __udivti3 __umodti3

ifdef CONFIG_ARM # Add eabi initrinsics for ARM 32-bit redirect-intrinsics +=
__aeabi_fadd __aeabi_fmul __aeabi_fcmpeq __aeabi_fcmple __aeabi_fcmplt __aeabi_fcmpun
__aeabi_dadd __aeabi_dmul __aeabi_dcmple __aeabi_dcmplt __aeabi_dcmpun
__aeabi_uldivmod endif ifneq ($(or $(CONFIG_ARM64),$(and $(CONFIG_RISCV),$(CONFIG_64BIT))),) # These intrinsics are defined for ARM64 and RISCV64 redirect-intrinsics +=
__ashrti3
__ashlti3 __lshrti3 endif

ifdef CONFIG_MODVERSIONS cmd_gendwarfksyms = $(if $(skip_gendwarfksyms),,
$(call rust_exports,$@,"%s\n") |
scripts/gendwarfksyms/gendwarfksyms
$(if $(KBUILD_GENDWARFKSYMS_STABLE), --stable)
$(if $(KBUILD_SYMTYPES), --symtypes $(@:.o=.symtypes),)
$@ >> $(dot-target).cmd) endif

define rule_rustc_library $(call cmd_and_fixdep,rustc_library) $(call cmd,gen_objtooldep) $(call cmd,gendwarfksyms) endef

define rule_rust_cc_library $(call if_changed_rule,cc_o_c) $(call cmd,force_checksrc) $(call cmd,gendwarfksyms) endef

helpers.o uses the same export mechanism as Rust libraries, so ensure symbol

versions are calculated for the helpers too.

$(obj)/helpers/helpers.o: $(src)/helpers/helpers.c $(recordmcount_source) FORCE +$(call if_changed_rule,rust_cc_library)

Disable symbol versioning for exports.o to avoid conflicts with the actual

symbol versions generated from Rust objects.

$(obj)/exports.o: private skip_gendwarfksyms = 1

$(obj)/core.o: private skip_clippy = 1 $(obj)/core.o: private skip_flags = --edition=2021 -Wunreachable_pub $(obj)/core.o: private rustc_objcopy = $(foreach sym,$(redirect-intrinsics),--redefine-sym $(sym)=__rust$(sym)) $(obj)/core.o: private rustc_target_flags = --edition=$(core-edition) $(core-cfgs) $(obj)/core.o: $(RUST_LIB_SRC)/core/src/lib.rs
$(wildcard $(objtree)/include/config/RUSTC_VERSION_TEXT) FORCE +$(call if_changed_rule,rustc_library) ifneq ($(or $(CONFIG_X86_64),$(CONFIG_X86_32)),) $(obj)/core.o: scripts/target.json endif KCOV_INSTRUMENT_core.o := n

$(obj)/compiler_builtins.o: private skip_gendwarfksyms = 1 $(obj)/compiler_builtins.o: private rustc_objcopy = -w -W '__*' $(obj)/compiler_builtins.o: $(src)/compiler_builtins.rs $(obj)/core.o FORCE +$(call if_changed_rule,rustc_library)

$(obj)/pin_init.o: private skip_gendwarfksyms = 1 $(obj)/pin_init.o: private rustc_target_flags = --extern pin_init_internal
--extern macros --cfg kernel $(obj)/pin_init.o: $(src)/pin-init/src/lib.rs $(obj)/compiler_builtins.o
$(obj)/$(libpin_init_internal_name) $(obj)/$(libmacros_name) FORCE +$(call if_changed_rule,rustc_library)

$(obj)/build_error.o: private skip_gendwarfksyms = 1 $(obj)/build_error.o: $(src)/build_error.rs $(obj)/compiler_builtins.o FORCE +$(call if_changed_rule,rustc_library)

$(obj)/ffi.o: private skip_gendwarfksyms = 1 $(obj)/ffi.o: $(src)/ffi.rs $(obj)/compiler_builtins.o FORCE +$(call if_changed_rule,rustc_library)

$(obj)/bindings.o: private rustc_target_flags = --extern ffi $(obj)/bindings.o: $(src)/bindings/lib.rs
$(obj)/ffi.o
$(obj)/bindings/bindings_generated.rs
$(obj)/bindings/bindings_helpers_generated.rs FORCE +$(call if_changed_rule,rustc_library)

$(obj)/uapi.o: private rustc_target_flags = --extern ffi $(obj)/uapi.o: private skip_gendwarfksyms = 1 $(obj)/uapi.o: $(src)/uapi/lib.rs
$(obj)/ffi.o
$(obj)/uapi/uapi_generated.rs FORCE +$(call if_changed_rule,rustc_library)

$(obj)/kernel.o: private rustc_target_flags = --extern ffi --extern pin_init
--extern build_error --extern macros --extern bindings --extern uapi $(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/build_error.o $(obj)/pin_init.o
$(obj)/$(libmacros_name) $(obj)/bindings.o $(obj)/uapi.o FORCE +$(call if_changed_rule,rustc_library)

ifdef CONFIG_JUMP_LABEL $(obj)/kernel.o: $(obj)/kernel/generated_arch_static_branch_asm.rs endif

endif # CONFIG_RUST