[PATCH v3] rust: query the compiler for dylib path

From: Tamir Duberstein
Date: Wed Oct 09 2024 - 10:16:44 EST


Rust proc-macro crates are loaded by the compiler at compile-time, so
are always dynamic libraries; on macOS, these artifacts get a .dylib
extension rather than .so.

Replace hardcoded paths ending in .so with paths obtained from the
compiler.

Co-developed-by: Fiona Behrens <me@xxxxxxxxxx>
Signed-off-by: Tamir Duberstein <tamird@xxxxxxxxx>
---
V2 -> V3: Added .strip() to rustc output to remove errant newline.
V1 -> V2: De-duplicated and sorted imports. Changed Signed-off-by to
Co-developed-by.

.gitignore | 1 +
Makefile | 2 +-
rust/Makefile | 21 ++++++++++++---------
scripts/generate_rust_analyzer.py | 15 +++++++++++----
4 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/.gitignore b/.gitignore
index a61e4778d011..088696a6a46a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,6 +22,7 @@
*.dtb.S
*.dtbo.S
*.dwo
+*.dylib
*.elf
*.gcno
*.gcda
diff --git a/Makefile b/Makefile
index a9e723cb0596..470e6f20c513 100644
--- a/Makefile
+++ b/Makefile
@@ -1513,7 +1513,7 @@ MRPROPER_FILES += include/config include/generated \
certs/x509.genkey \
vmlinux-gdb.py \
rpmbuild \
- rust/libmacros.so
+ rust/libmacros.so rust/libmacros.dylib

# clean - Delete most, but leave enough to build external modules
#
diff --git a/rust/Makefile b/rust/Makefile
index 0856fd6bc610..94ae550ae8b3 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -11,9 +11,6 @@ always-$(CONFIG_RUST) += exports_core_generated.h
obj-$(CONFIG_RUST) += helpers/helpers.o
CFLAGS_REMOVE_helpers/helpers.o = -Wmissing-prototypes -Wmissing-declarations

-always-$(CONFIG_RUST) += libmacros.so
-no-clean-files += libmacros.so
-
always-$(CONFIG_RUST) += bindings/bindings_generated.rs bindings/bindings_helpers_generated.rs
obj-$(CONFIG_RUST) += alloc.o bindings.o kernel.o
always-$(CONFIG_RUST) += exports_alloc_generated.h exports_helpers_generated.h \
@@ -36,9 +33,15 @@ 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

-# Avoids running `$(RUSTC)` for the sysroot when it may not be available.
+# Avoids running `$(RUSTC)` when it may not be available.
ifdef CONFIG_RUST

+libmacros_name := $($(RUSTC) --print file-names --crate-name macros --crate-type proc-macro - < /dev/null)
+libmacros_extension := $(patsubst libmacros.%,%,$(libmacros_name))
+
+always-$(CONFIG_RUST) += $(libmacros_name)
+no-clean-files += $(libmacros_name)
+
# `$(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)
@@ -118,10 +121,10 @@ rustdoc-alloc: $(RUST_LIB_SRC)/alloc/src/lib.rs rustdoc-core rustdoc-compiler_bu
+$(call if_changed,rustdoc)

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

@@ -342,10 +345,10 @@ quiet_cmd_rustc_procmacro = $(RUSTC_OR_CLIPPY_QUIET) P $@
-Clink-args='$(call escsq,$(KBUILD_HOSTLDFLAGS))' \
--emit=dep-info=$(depfile) --emit=link=$@ --extern proc_macro \
--crate-type proc-macro \
- --crate-name $(patsubst lib%.so,%,$(notdir $@)) $<
+ --crate-name $(patsubst lib%.$(libmacros_extension),%,$(notdir $@)) $<

# Procedural macros can only be used with the `rustc` that compiled it.
-$(obj)/libmacros.so: $(src)/macros/lib.rs FORCE
+$(obj)/$(libmacros_name): $(src)/macros/lib.rs FORCE
+$(call if_changed_dep,rustc_procmacro)

quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L $@
@@ -424,7 +427,7 @@ $(obj)/uapi.o: $(src)/uapi/lib.rs \
$(obj)/kernel.o: private rustc_target_flags = --extern alloc \
--extern build_error --extern macros --extern bindings --extern uapi
$(obj)/kernel.o: $(src)/kernel/lib.rs $(obj)/alloc.o $(obj)/build_error.o \
- $(obj)/libmacros.so $(obj)/bindings.o $(obj)/uapi.o FORCE
+ $(obj)/$(libmacros_name) $(obj)/bindings.o $(obj)/uapi.o FORCE
+$(call if_changed_rule,rustc_library)

endif # CONFIG_RUST
diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_analyzer.py
index d2bc63cde8c6..04ff5b25b851 100755
--- a/scripts/generate_rust_analyzer.py
+++ b/scripts/generate_rust_analyzer.py
@@ -8,6 +8,7 @@ import json
import logging
import os
import pathlib
+import subprocess
import sys

def args_crates_cfgs(cfgs):
@@ -35,8 +36,7 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs):
crates_cfgs = args_crates_cfgs(cfgs)

def append_crate(display_name, root_module, deps, cfg=[], is_workspace_member=True, is_proc_macro=False):
- crates_indexes[display_name] = len(crates)
- crates.append({
+ crate = {
"display_name": display_name,
"root_module": str(root_module),
"is_workspace_member": is_workspace_member,
@@ -47,7 +47,15 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs):
"env": {
"RUST_MODFILE": "This is only for rust-analyzer"
}
- })
+ }
+ if is_proc_macro:
+ proc_macro_dylib_name = subprocess.check_output(
+ [os.environ["RUSTC"], "--print", "file-names", "--crate-name", display_name, "--crate-type", "proc-macro", "-"],
+ stdin=subprocess.DEVNULL,
+ ).decode('utf-8').strip()
+ crate["proc_macro_dylib_path"] = f"{objtree}/rust/{proc_macro_dylib_name}"
+ crates_indexes[display_name] = len(crates)
+ crates.append(crate)

# First, the ones in `rust/` since they are a bit special.
append_crate(
@@ -77,7 +85,6 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs):
[],
is_proc_macro=True,
)
- crates[-1]["proc_macro_dylib_path"] = f"{objtree}/rust/libmacros.so"

append_crate(
"build_error",
--
2.47.0