Merge tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - Convert sh and sparc to use generic shell scripts to generate the
   syscall headers

 - refactor .gitignore files

 - Update kernel/config_data.gz only when the content of the .config
   is really changed, which avoids the unneeded re-link of vmlinux

 - move "remove stale files" workarounds to scripts/remove-stale-files

 - suppress unused-but-set-variable warnings by default for Clang
   as well

 - fix locale setting LANG=C to LC_ALL=C

 - improve 'make distclean'

 - always keep intermediate objects from scripts/link-vmlinux.sh

 - move IF_ENABLED out of <linux/kconfig.h> to make it self-contained

 - misc cleanups

* tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits)
  linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>
  kbuild: Don't remove link-vmlinux temporary files on exit/signal
  kbuild: remove the unneeded comments for external module builds
  kbuild: make distclean remove tag files in sub-directories
  kbuild: make distclean work against $(objtree) instead of $(srctree)
  kbuild: refactor modname-multi by using suffix-search
  kbuild: refactor fdtoverlay rule
  kbuild: parameterize the .o part of suffix-search
  arch: use cross_compiling to check whether it is a cross build or not
  kbuild: remove ARCH=sh64 support from top Makefile
  .gitignore: prefix local generated files with a slash
  kbuild: replace LANG=C with LC_ALL=C
  Makefile: Move -Wno-unused-but-set-variable out of GCC only block
  kbuild: add a script to remove stale generated files
  kbuild: update config_data.gz only when the content of .config is changed
  .gitignore: ignore only top-level modules.builtin
  .gitignore: move tags and TAGS close to other tag files
  kernel/.gitgnore: remove stale timeconst.h and hz.bc
  usr/include: refactor .gitignore
  genksyms: fix stale comment
  ...

1 files changed, 30 insertions, 27 deletions

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 64daf37e874b..10950559b223 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -44,19 +44,22 @@ else
 obj-y		:= $(filter-out %/, $(obj-y))
 endif
 
-# Expand $(foo-objs) $(foo-y) by calling $(call suffix-search,foo.o,-objs -y)
-suffix-search = $(strip $(foreach s, $2, $($(1:.o=$s))))
+# Expand $(foo-objs) $(foo-y) etc. by replacing their individuals
+suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s))))
+# List composite targets that are constructed by combining other targets
+multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m)))
+# List primitive targets that are compiled from source files
+real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m))
+
 # If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
-multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2 -), $m)))
-multi-obj-y := $(call multi-search,$(obj-y),-objs -y)
-multi-obj-m := $(call multi-search,$(obj-m),-objs -y -m)
+multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y)
+multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m)
 multi-obj-ym := $(multi-obj-y) $(multi-obj-m)
 
 # Replace multi-part objects by their individual parts,
 # including built-in.a from subdirectories
-real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2 -), $(call suffix-search, $m, $2), $m))
-real-obj-y := $(call real-search, $(obj-y),-objs -y)
-real-obj-m := $(call real-search, $(obj-m),-objs -y -m)
+real-obj-y := $(call real-search, $(obj-y), .o, -objs -y)
+real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m)
 
 always-y += $(always-m)
 
@@ -75,24 +78,18 @@ always-y += $(userprogs-always-y) $(userprogs-always-m)
 # If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
 dtb-$(CONFIG_OF_ALL_DTBS)       += $(dtb-)
 
-# List all dtbs to be generated by fdtoverlay
-overlay-y := $(foreach m,$(dtb-y), $(if $(strip $($(m:.dtb=-dtbs))),$(m),))
-
-# Generate symbols for the base files so overlays can be applied to them.
-$(foreach m,$(overlay-y), $(eval DTC_FLAGS_$(basename $(firstword $($(m:.dtb=-dtbs)))) += -@))
-
-# Add base dtb and overlay dtbo
-dtb-y += $(foreach m,$(overlay-y), $($(m:.dtb=-dtbs)))
+# Composite DTB (i.e. DTB constructed by overlay)
+multi-dtb-y := $(call multi-search, $(dtb-y), .dtb, -dtbs)
+# Primitive DTB compiled from *.dts
+real-dtb-y := $(call real-search, $(dtb-y), .dtb, -dtbs)
+# Base DTB that overlay is applied onto (each first word of $(*-dtbs) expansion)
+base-dtb-y := $(foreach m, $(multi-dtb-y), $(firstword $(call suffix-search, $m, .dtb, -dtbs)))
 
 always-y			+= $(dtb-y)
 
 ifneq ($(CHECK_DTBS),)
-# Don't run schema checks for dtbs created by fdtoverlay as they don't
-# have corresponding dts files.
-dt-yaml-y := $(filter-out $(overlay-y),$(dtb-y))
-
-always-y += $(patsubst %.dtb,%.dt.yaml, $(dt-yaml-y))
-always-y += $(patsubst %.dtbo,%.dt.yaml, $(dt-yaml-y))
+always-y += $(patsubst %.dtb,%.dt.yaml, $(real-dtb-y))
+always-y += $(patsubst %.dtbo,%.dt.yaml, $(real-dtb-y))
 endif
 
 # Add subdir path
@@ -105,12 +102,14 @@ lib-y		:= $(addprefix $(obj)/,$(lib-y))
 real-obj-y	:= $(addprefix $(obj)/,$(real-obj-y))
 real-obj-m	:= $(addprefix $(obj)/,$(real-obj-m))
 multi-obj-m	:= $(addprefix $(obj)/, $(multi-obj-m))
+multi-dtb-y	:= $(addprefix $(obj)/, $(multi-dtb-y))
+real-dtb-y	:= $(addprefix $(obj)/, $(real-dtb-y))
 subdir-ym	:= $(addprefix $(obj)/,$(subdir-ym))
 
 # Finds the multi-part object the current object will be linked into.
 # If the object belongs to two or more multi-part objects, list them all.
 modname-multi = $(sort $(foreach m,$(multi-obj-ym),\
-		$(if $(filter $*.o, $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$(m:.o=))))
+		$(if $(filter $*.o, $(call suffix-search, $m, .o, -objs -y -m)),$(m:.o=))))
 
 __modname = $(if $(modname-multi),$(modname-multi),$(basetarget))
 
@@ -252,6 +251,9 @@ quiet_cmd_copy = COPY    $@
 
 # Shipped files
 # ===========================================================================
+# 'cp' preserves permissions. If you use it to copy a file in read-only srctree,
+# the copy would be read-only as well, leading to an error when executing the
+# rule next time. Use 'cat' instead in order to generate a writable file.
 
 quiet_cmd_shipped = SHIPPED $@
 cmd_shipped = cat $< > $@
@@ -319,6 +321,9 @@ endif
 
 DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
 
+# Set -@ if the target is a base DTB that overlay is applied onto
+DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@)
+
 # Generate an assembly file to wrap the output of the device tree compiler
 quiet_cmd_dt_S_dtb= DTB     $@
 cmd_dt_S_dtb=						\
@@ -350,14 +355,12 @@ $(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
 $(obj)/%.dtbo: $(src)/%.dts $(DTC) FORCE
 	$(call if_changed_dep,dtc)
 
-overlay-y := $(addprefix $(obj)/, $(overlay-y))
-
 quiet_cmd_fdtoverlay = DTOVL   $@
       cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(real-prereqs)
 
-$(overlay-y): FORCE
+$(multi-dtb-y): FORCE
 	$(call if_changed,fdtoverlay)
-$(call multi_depend, $(overlay-y), .dtb, -dtbs)
+$(call multi_depend, $(multi-dtb-y), .dtb, -dtbs)
 
 DT_CHECKER ?= dt-validate
 DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),,-m)