make section names plural

Documentation/rust/general-information.rst

@@ -151,3 +151,11 @@ configuration:
  #[cfg(CONFIG_X="y")] // Enabled as a built-in (`y`)
  #[cfg(CONFIG_X="m")] // Enabled as a module (`m`)
  #[cfg(not(CONFIG_X))] // Disabled
+
+For other predicates that Rust's ``cfg`` does not support, e.g. expressions with
+numerical comparisons, one may define a new Kconfig symbol:
+
+.. code-block:: kconfig
+
+ config RUSTC_VERSION_MIN_107900
+ def_bool y if RUSTC_VERSION >= 107900

Makefile

@@ -648,9 +648,11 @@ endif
 
 # The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
 # Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
-# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
-# and from include/config/auto.conf.cmd to detect the compiler upgrade.
+# CC_VERSION_TEXT and RUSTC_VERSION_TEXT are referenced from Kconfig (so they
+# need export), and from include/config/auto.conf.cmd to detect the compiler
+# upgrade.
 CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
+RUSTC_VERSION_TEXT = $(subst $(pound),,$(shell $(RUSTC) --version 2>/dev/null))
 
 ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
 include $(srctree)/scripts/Makefile.clang
@@ -671,7 +673,7 @@ ifdef config-build
 # KBUILD_DEFCONFIG may point out an alternative default configuration
 # used for 'make defconfig'
 include $(srctree)/arch/$(SRCARCH)/Makefile
-export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
+export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT RUSTC_VERSION_TEXT
 
 config: outputmakefile scripts_basic FORCE
  $(Q)$(MAKE) $(build)=scripts/kconfig $@

init/Kconfig

@@ -60,6 +60,13 @@ config LLD_VERSION
  default $(ld-version) if LD_IS_LLD
  default 0
 
+config RUSTC_VERSION
+ int
+ default $(shell,$(srctree)/scripts/rustc-version.sh $(RUSTC))
+ help
+ It does not depend on `RUST` since that one may need to use the version
+ in a `depends on`.
+
 config RUST_IS_AVAILABLE
  def_bool $(success,$(srctree)/scripts/rust_is_available.sh)
  help
@@ -1920,7 +1927,9 @@ config RUST
 config RUSTC_VERSION_TEXT
  string
  depends on RUST
- default "$(shell,$(RUSTC) --version 2>/dev/null)"
+ default "$(RUSTC_VERSION_TEXT)"
+ help
+ See `CC_VERSION_TEXT`.
 
 config BINDGEN_VERSION_TEXT
  string

rust/Makefile

@@ -342,9 +342,7 @@ quiet_cmd_rustc_procmacro = $(RUSTC_OR_CLIPPY_QUIET) P $@
  --crate-name $(patsubst lib%.so,%,$(notdir $@)) $<
 
 # Procedural macros can only be used with the `rustc` that compiled it.
-# Therefore, to get `libmacros.so` automatically recompiled when the compiler
-# version changes, we add `core.o` as a dependency (even if it is not needed).
-$(obj)/libmacros.so: $(src)/macros/lib.rs $(obj)/core.o FORCE
+$(obj)/libmacros.so: $(src)/macros/lib.rs FORCE
  +$(call if_changed_dep,rustc_procmacro)
 
 quiet_cmd_rustc_library = $(if $(skip_clippy),RUSTC,$(RUSTC_OR_CLIPPY_QUIET)) L $@
@@ -389,7 +387,8 @@ $(obj)/core.o: private skip_clippy = 1
 $(obj)/core.o: private skip_flags = -Wunreachable_pub
 $(obj)/core.o: private rustc_objcopy = $(foreach sym,$(redirect-intrinsics),--redefine-sym $(sym)=__rust$(sym))
 $(obj)/core.o: private rustc_target_flags = $(core-cfgs)
-$(obj)/core.o: $(RUST_LIB_SRC)/core/src/lib.rs FORCE
+$(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

rust/kernel/init.rs

@@ -746,7 +746,7 @@ macro_rules! try_init {
 /// Asserts that a field on a struct using `#[pin_data]` is marked with `#[pin]` ie. that it is
 /// structurally pinned.
 ///
-/// # Example
+/// # Examples
 ///
 /// This will succeed:
 /// ```

rust/kernel/list/arc.rs

@@ -464,7 +464,7 @@ where
 
 /// A utility for tracking whether a [`ListArc`] exists using an atomic.
 ///
-/// # Invariant
+/// # Invariants
 ///
 /// If the boolean is `false`, then there is no [`ListArc`] for this value.
 #[repr(transparent)]

rust/kernel/sync/arc.rs

@@ -436,7 +436,7 @@ impl<T: ?Sized> From<Pin<UniqueArc<T>>> for Arc<T> {
 /// There are no mutable references to the underlying [`Arc`], and it remains valid for the
 /// lifetime of the [`ArcBorrow`] instance.
 ///
-/// # Example
+/// # Examples
 ///
 /// ```
 /// use kernel::sync::{Arc, ArcBorrow};

rust/macros/lib.rs

@@ -2,6 +2,10 @@
 
 //! Crate for all kernel procedural macros.
 
+// When fixdep scans this, it will find this string `CONFIG_RUSTC_VERSION_TEXT`
+// and thus add a dependency on `include/config/RUSTC_VERSION_TEXT`, which is
+// touched by Kconfig when the version string from the compiler changes.
+
 #[macro_use]
 mod quote;
 mod concat_idents;
@@ -303,7 +307,7 @@ pub fn pinned_drop(args: TokenStream, input: TokenStream) -> TokenStream {
 /// literals (lifetimes and documentation strings are not supported). There is a difference in
 /// supported modifiers as well.
 ///
-/// # Example
+/// # Examples
 ///
 /// ```ignore
 /// use kernel::macro::paste;

scripts/checkpatch.pl

@@ -3900,6 +3900,13 @@ sub process {
  "Avoid using '.L' prefixed local symbol names for denoting a range of code via 'SYM_*_START/END' annotations; see Documentation/core-api/asm-annotations.rst\n" . $herecurr);
  }
 
+# check that document section headers are plural in rust files
+ if ($realfile =~ /\.rs$/
+ && $rawline =~ /^\+\s*\/\/\/\s+#+\s+(Example|Invariant|Guarantee|Panic)\s*$/) {
+ WARN( "RUST_DOC_HEADER",
+ "Rust doc headers should be plural\n" . $herecurr );
+ }
+
 # check we are in a valid source file C or perl if not then ignore this hunk
  next if ($realfile !~ /\.(h|c|pl|dtsi|dts)$/);
 

scripts/rustc-version.sh

@@ -0,0 +1,26 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Usage: $ ./rustc-version.sh rustc
+#
+# Print the Rust compiler name and its version in a 6 or 7-digit form.
+
+# Convert the version string x.y.z to a canonical up-to-7-digits form.
+#
+# Note that this function uses one more digit (compared to other
+# instances in other version scripts) to give a bit more space to
+# `rustc` since it will reach 1.100.0 in late 2026.
+get_canonical_version()
+{
+ IFS=.
+ set -- $1
+ echo $((100000 * $1 + 100 * $2 + $3))
+}
+
+if output=$("$@" --version 2>/dev/null); then
+ set -- $output
+ get_canonical_version $2
+else
+ echo 0
+ exit 1
+fi