Merge tag 'kbuild-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux

Pull Kbuild / Kconfig updates from Nathan Chancellor:
 "Kbuild:

   - Remove broken module linking exclusion for BTF

   - Add documentation around how offset header files work

   - Include unstripped vDSO libraries in pacman packages

   - Bump minimum version of LLVM for building the kernel to 17.0.1 and
     clean up unnecessary workarounds

   - Use a context manager in run-clang-tools

   - Add dist macro value if present to release tag for RPM packages

   - Detect and report truncated buf_printf() output in modpost

   - Add __llvm_covfun and __llvm_covmap to section whitelist in modpost

   - Support Clang's distributed ThinLTO mode

   - Remove architecture specific configurations for AutoFDO and
     Propeller to ease individual architecture maintenance

  Kconfig:

   - Add kconfig-sym-check target to look for dangling Kconfig symbol
     references and invalid tristate literal values

   - Harden against potential NULL pointer dereference

   - Fix typo in Kconfig test comment"

* tag 'kbuild-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (31 commits)
  kconfig: tests: fix typo in comment
  kconfig: Remove the architecture specific config for Propeller
  kconfig: Remove the architecture specific config for AutoFDO
  modpost: Add __llvm_covfun and __llvm_covmap to section_white_list
  kconfig: add kconfig-sym-check static checker
  kbuild: Remove unnecessary 'T' modifier in cmd_ar_builtin_fixup
  kbuild: distributed build support for Clang ThinLTO
  kbuild: move vmlinux.a build rule to scripts/Makefile.vmlinux_a
  scripts: modpost: detect and report truncated buf_printf() output
  kbuild: rpm-pkg: append %{?dist} macro to Release tag
  run-clang-tools: run multiprocessing.Pool as context manager
  compiler-clang.h: Drop explicit version number from "all" diagnostic macro
  compiler-clang.h: Remove __cleanup -Wunused-variable workaround
  kbuild: Remove check for broken scoping with clang < 17 in CC_HAS_ASM_GOTO_OUTPUT
  x86/entry/vdso32: Remove conditional omission of '.cfi_offset eflags'
  x86/module: Revert "Deal with GOT based stack cookie load on Clang < 17"
  x86/build: Drop unnecessary '-ffreestanding' addition to KBUILD_CFLAGS
  scripts/Makefile.warn: Drop -Wformat handling for clang < 16
  riscv: Drop tautological condition from TOOLCHAIN_NEEDS_OLD_ISA_SPEC
  riscv: Remove tautological condition from selection of ARCH_SUPPORTS_CFI
  ...

1 files changed, 40 insertions, 0 deletions

diff --git a/scripts/Makefile.thinlto b/scripts/Makefile.thinlto
new file mode 100644
index 000000000000..bb83f13f3cd6
--- /dev/null
+++ b/scripts/Makefile.thinlto
@@ -0,0 +1,40 @@
+PHONY := __default
+__default:
+
+include include/config/auto.conf
+include $(srctree)/scripts/Kbuild.include
+include $(srctree)/scripts/Makefile.lib
+
+native-objs := $(patsubst %.o,%.thinlto-native.o,$(call read-file, vmlinux.thinlto-index))
+
+__default: $(native-objs)
+
+# Generate .thinlto-native.o (obj) from .o (bitcode) and .thinlto.bc (summary) files
+# ---------------------------------------------------------------------------
+quiet_cmd_cc_o_bc = CC $(quiet_modtag)  $@
+      be_flags = $(shell sed -n '/saved_c_flags_/s/.*:= //p' \
+                $(dir $(<)).$(notdir $(<)).cmd)
+      cmd_cc_o_bc = \
+      $(CC) $(be_flags) -x ir -fno-lto -Wno-unused-command-line-argument \
+      -fthinlto-index=$(word 2, $^) -c -o $@ $<
+
+targets += $(native-objs)
+$(native-objs): %.thinlto-native.o: %.o %.o.thinlto.bc   FORCE
+	$(call if_changed,cc_o_bc)
+
+# Add FORCE to the prerequisites of a target to force it to be always rebuilt.
+# ---------------------------------------------------------------------------
+
+PHONY += FORCE
+FORCE:
+
+# Read all saved command lines and dependencies for the $(targets) we
+# may be building above, using $(if_changed{,_dep}). As an
+# optimization, we don't need to read them if the target does not
+# exist, we will rebuild anyway in that case.
+
+existing-targets := $(wildcard $(sort $(targets)))
+
+-include $(foreach f, $(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
+
+.PHONY: $(PHONY)