Merge patch series "kbuild: Update Makefile.extrawarn to 5.1"

This series from Ilias Apalodimas <[email protected]> largely
finishes the re-sync with the Linux Kernel v5.1 kbuild system.

Link: https://lore.kernel.org/r/[email protected]

6 files changed, 349 insertions, 128 deletions

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index aa48d249433..998679f00a0 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -76,10 +76,12 @@ endif
 
 ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
 lib-target := $(obj)/lib.a
+# Modified for U-Boot
+# real-obj-y += $(obj)/lib-ksyms.o
 endif
 
-ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
-builtin-target := $(obj)/built-in.o
+ifneq ($(strip $(real-obj-y) $(need-builtin)),)
+builtin-target := $(obj)/built-in.a
 endif
 
 ifdef CONFIG_MODULES
@@ -102,7 +104,11 @@ else ifeq ($(KBUILD_CHECKSRC),2)
         cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $<
 endif
 
-# Do section mismatch analysis for each module/built-in.o
+ifneq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),)
+  cmd_checkdoc = $(srctree)/scripts/kernel-doc -none $<
+endif
+
+# Do section mismatch analysis for each module/built-in.a
 ifdef CONFIG_DEBUG_SECTION_MISMATCH
   cmd_secanalysis = ; scripts/mod/modpost $@
 endif
@@ -111,101 +117,94 @@ endif
 # ---------------------------------------------------------------------------
 
 # Default is built-in, unless we know otherwise
+$(foreach x, i ll lst o s symtypes, $(patsubst %.o,%.$(x),$(real-obj-m))): \
+	part-of-module := y
+
 modkern_cflags =                                          \
 	$(if $(part-of-module),                           \
 		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 		$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
 quiet_modtag = $(if $(part-of-module),[M],   )
 
-$(real-objs-m)        : part-of-module := y
-$(real-objs-m:.o=.i)  : part-of-module := y
-$(real-objs-m:.o=.s)  : part-of-module := y
-$(real-objs-m:.o=.lst): part-of-module := y
-
-# Default for not multi-part modules
-modname = $(basetarget)
-
-$(multi-objs-m)         : modname = $(modname-multi)
-$(multi-objs-m:.o=.i)   : modname = $(modname-multi)
-$(multi-objs-m:.o=.s)   : modname = $(modname-multi)
-$(multi-objs-m:.o=.lst) : modname = $(modname-multi)
-$(multi-objs-y)         : modname = $(modname-multi)
-$(multi-objs-y:.o=.i)   : modname = $(modname-multi)
-$(multi-objs-y:.o=.s)   : modname = $(modname-multi)
-$(multi-objs-y:.o=.lst) : modname = $(modname-multi)
-
 quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
-cmd_cc_s_c       = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
+      cmd_cc_s_c = $(CC) $(filter-out $(DEBUG_CFLAGS), $(c_flags)) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
 
 $(obj)/%.s: $(src)/%.c FORCE
 	$(call if_changed_dep,cc_s_c)
 
-quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@
-cmd_cc_i_c       = $(CPP) $(c_flags)   -o $@ $<
+quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
+cmd_cpp_i_c       = $(CPP) $(c_flags) -o $@ $<
 
 $(obj)/%.i: $(src)/%.c FORCE
-	$(call if_changed_dep,cc_i_c)
+	$(call if_changed_dep,cpp_i_c)
 
-cmd_gensymtypes =                                                           \
+# These mirror gensymtypes_S and co below, keep them in synch.
+cmd_gensymtypes_c =                                                         \
     $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
-    scripts/genksyms/genksyms $(if $(1), -T $(2))			    \
+    scripts/genksyms/genksyms $(if $(1), -T $(2))                           \
+     $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
      $(if $(KBUILD_PRESERVE),-p)                                            \
      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 
 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
 cmd_cc_symtypes_c =                                                         \
-    $(call cmd_gensymtypes,true,$@) >/dev/null;                             \
+    $(call cmd_gensymtypes_c,true,$@) >/dev/null;                           \
     test -s $@ || rm -f $@
 
 $(obj)/%.symtypes : $(src)/%.c FORCE
 	$(call cmd,cc_symtypes_c)
 
+# LLVM assembly
+# Generate .ll files from .c
+quiet_cmd_cc_ll_c = CC $(quiet_modtag)  $@
+      cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -o $@ $<
+
+$(obj)/%.ll: $(src)/%.c FORCE
+	$(call if_changed_dep,cc_ll_c)
+
 # C (.c) files
 # The C file is compiled and updated dependency information is generated.
 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
 
 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
-cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
+      cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 
 ifdef CONFIG_MODVERSIONS
 # When module versioning is enabled the following steps are executed:
 # o compile a <file>.o from <file>.c
 # o if <file>.o doesn't contain a __ksymtab version, i.e. does
-#   not export symbols, it's done
+#   not export symbols, it's done.
 # o otherwise, we calculate symbol versions using the good old
 #   genksyms on the preprocessed source and postprocess them in a way
 #   that they are usable as a linker script
 # o generate .tmp_<file>.o from <file>.o using the linker to
 #   replace the unresolved symbols __crc_exported_symbol with
 #   the actual value of the checksum generated by genksyms
-
 # o remove .tmp_<file>.o to <file>.o
-cmd_modversions =								\
+
+cmd_modversions_c =								\
 	if $(OBJDUMP) -h $@ | grep -q __ksymtab; then				\
-		$(call cmd_gensymtypes,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\
+		$(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\
 		    > $(@D)/.tmp_$(@F:.o=.ver);					\
 										\
-		$(LD) $(KBUILD_LDFLAGS) -r -o $(@D)/.tmp_$(@F) $@		\
+		$(LD) $(KBUILD_LDFLAGS) -r -o $(@D)/.tmp_$(@F) $@ 		\
 			-T $(@D)/.tmp_$(@F:.o=.ver);				\
 		mv -f $(@D)/.tmp_$(@F) $@;					\
 		rm -f $(@D)/.tmp_$(@F:.o=.ver);					\
-	fi;
+	fi
 endif
 
 ifdef CONFIG_FTRACE_MCOUNT_RECORD
-# gcc 5 supports generating the mcount tables directly
-ifneq ($(call cc-option,-mrecord-mcount,y),y)
-KBUILD_CFLAGS += -mrecord-mcount
-else
-# else do it all manually
+ifndef CC_USING_RECORD_MCOUNT
+# compiler will not generate __mcount_loc use recordmcount or recordmcount.pl
 ifdef BUILD_C_RECORDMCOUNT
 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
   RECORDMCOUNT_FLAGS = -w
 endif
 # Due to recursion, we must skip empty.o.
 # The empty.o file is created in the make process in order to determine
-#  the target endianness and word size. It is made before all other C
-#  files, including recordmcount.
+# the target endianness and word size. It is made before all other C
+# files, including recordmcount.
 sub_cmd_record_mcount =					\
 	if [ $(@) != "scripts/mod/empty.o" ]; then	\
 		$(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";	\
@@ -213,17 +212,59 @@ sub_cmd_record_mcount =					\
 recordmcount_source := $(srctree)/scripts/recordmcount.c \
 		    $(srctree)/scripts/recordmcount.h
 else
-sub_cmd_record_mcount = perl $(srctree)/scripts/recordmcount.pl "$(ARCH)"	\
+sub_cmd_record_mcount = perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
 	"$(if $(CONFIG_SYS_BIG_ENDIAN),big,little)" \
 	"$(if $(CONFIG_64BIT),64,32)" \
 	"$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS)" \
 	"$(LD) $(KBUILD_LDFLAGS)" "$(NM)" "$(RM)" "$(MV)" \
 	"$(if $(part-of-module),1,0)" "$(@)";
 recordmcount_source := $(srctree)/scripts/recordmcount.pl
+endif # BUILD_C_RECORDMCOUNT
+cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)),	\
+	$(sub_cmd_record_mcount))
+endif # CC_USING_RECORD_MCOUNT
+endif # CONFIG_FTRACE_MCOUNT_RECORD
+
+ifdef CONFIG_STACK_VALIDATION
+ifneq ($(SKIP_STACK_VALIDATION),1)
+
+__objtool_obj := $(objtree)/tools/objtool/objtool
+
+objtool_args = $(if $(CONFIG_UNWINDER_ORC),orc generate,check)
+
+objtool_args += $(if $(part-of-module), --module,)
+
+ifndef CONFIG_FRAME_POINTER
+objtool_args += --no-fp
 endif
-cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)),        \
-       $(sub_cmd_record_mcount))
-endif # -record-mcount
+ifdef CONFIG_GCOV_KERNEL
+objtool_args += --no-unreachable
+endif
+ifdef CONFIG_RETPOLINE
+  objtool_args += --retpoline
+endif
+
+# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
+# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
+# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
+cmd_objtool = $(if $(patsubst y%,, \
+	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
+	$(__objtool_obj) $(objtool_args) $@)
+objtool_obj = $(if $(patsubst y%,, \
+	$(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
+	$(__objtool_obj))
+
+endif # SKIP_STACK_VALIDATION
+endif # CONFIG_STACK_VALIDATION
+
+# Rebuild all objects when objtool changes, or is enabled/disabled.
+objtool_dep = $(objtool_obj)					\
+	      $(wildcard include/config/orc/unwinder.h		\
+			 include/config/stack/validation.h)
+
+ifdef CONFIG_TRIM_UNUSED_KSYMS
+cmd_gen_ksymdeps = \
+	$(CONFIG_SHELL) $(srctree)/scripts/gen_ksymdeps.sh $@ >> $(dot-target).cmd
 endif
 
 define rule_cc_o_c
@@ -243,17 +284,25 @@ define rule_as_o_S
 	$(call cmd,modversions_S)
 endef
 
+# List module undefined symbols (or empty line if not enabled)
+ifdef CONFIG_TRIM_UNUSED_KSYMS
+cmd_undef_syms = $(NM) $@ | sed -n 's/^  *U //p' | xargs echo
+else
+cmd_undef_syms = echo
+endif
+
 # Built-in and composite module parts
-$(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
+$(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
 	$(call cmd,force_checksrc)
 	$(call if_changed_rule,cc_o_c)
 
 # Single-part modules are special since we need to mark them in $(MODVERDIR)
 
-$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
+$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
 	$(call cmd,force_checksrc)
 	$(call if_changed_rule,cc_o_c)
-	@{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod)
+	@{ echo $(@:.o=.ko); echo $@; \
+	   $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
 
 quiet_cmd_cc_lst_c = MKLST   $@
       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
@@ -268,29 +317,83 @@ $(obj)/%.lst: $(src)/%.c FORCE
 
 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
 
-$(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
-$(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
+$(real-obj-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
+$(real-obj-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
+
+# .S file exports must have their C prototypes defined in asm/asm-prototypes.h
+# or a file that it includes, in order to get versioned symbols. We build a
+# dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
+# the .S file (with trailing ';'), and run genksyms on that, to extract vers.
+#
+# This is convoluted. The .S file must first be preprocessed to run guards and
+# expand names, then the resulting exports must be constructed into plain
+# EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
+# to make the genksyms input.
+#
+# These mirror gensymtypes_c and co above, keep them in synch.
+cmd_gensymtypes_S =                                                         \
+   { echo "\#include <linux/kernel.h>" ;                                    \
+     echo "\#include <asm/asm-prototypes.h>" ;                              \
+    $(CPP) $(a_flags) $< |                                                  \
+     grep "\<___EXPORT_SYMBOL\>" |                                          \
+     sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ; } | \
+    $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
+    scripts/genksyms/genksyms $(if $(1), -T $(2))                           \
+     $(patsubst y,-R,$(CONFIG_MODULE_REL_CRCS))                             \
+     $(if $(KBUILD_PRESERVE),-p)                                            \
+     -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
+
+quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
+cmd_cc_symtypes_S =                                                         \
+    $(call cmd_gensymtypes_S,true,$@) >/dev/null;                           \
+    test -s $@ || rm -f $@
 
-quiet_cmd_as_s_S = CPP $(quiet_modtag) $@
-cmd_as_s_S       = $(CPP) $(a_flags)   -o $@ $<
+$(obj)/%.symtypes : $(src)/%.S FORCE
+	$(call cmd,cc_symtypes_S)
+
+
+quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
+cmd_cpp_s_S       = $(CPP) $(a_flags) -o $@ $<
 
 $(obj)/%.s: $(src)/%.S FORCE
-	$(call if_changed_dep,as_s_S)
+	$(call if_changed_dep,cpp_s_S)
 
 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
-cmd_as_o_S       = $(CC) $(a_flags) -c -o $@ $<
+      cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
+
+ifdef CONFIG_MODVERSIONS
+
+ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
 
-$(obj)/%.o: $(src)/%.S FORCE
-	$(call if_changed_dep,as_o_S)
+ifneq ($(ASM_PROTOTYPES),)
 
-targets += $(real-objs-y) $(real-objs-m) $(lib-y)
+# versioning matches the C process described above, with difference that
+# we parse asm-prototypes.h C header to get function definitions.
+
+cmd_modversions_S =								\
+	if $(OBJDUMP) -h $@ | grep -q __ksymtab; then				\
+		$(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))	\
+		    > $(@D)/.tmp_$(@F:.o=.ver);					\
+										\
+		$(LD) $(KBUILD_LDFLAGS) -r -o $(@D)/.tmp_$(@F) $@ 		\
+			-T $(@D)/.tmp_$(@F:.o=.ver);				\
+		mv -f $(@D)/.tmp_$(@F) $@;					\
+		rm -f $(@D)/.tmp_$(@F:.o=.ver);					\
+	fi
+endif
+endif
+
+$(obj)/%.o: $(src)/%.S $(objtool_dep) FORCE
+	$(call if_changed_rule,as_o_S)
+
+targets += $(filter-out $(subdir-obj-y), $(real-obj-y)) $(real-obj-m) $(lib-y)
 targets += $(extra-y) $(MAKECMDGOALS) $(always)
 targets += $(real-dtb-y) $(lib-y) $(always-y)
 
 # Linker scripts preprocessor (.lds.S -> .lds)
 # ---------------------------------------------------------------------------
 quiet_cmd_cpp_lds_S = LDS     $@
-      cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
+      cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -U$(ARCH) \
 	                     -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
 
 $(obj)/%.lds: $(src)/%.lds.S FORCE
@@ -312,17 +415,17 @@ $(obj)/%.asn1.c $(obj)/%.asn1.h: $(src)/%.asn1 $(objtree)/tools/asn1_compiler
 $(sort $(subdir-obj-y)): $(subdir-ym) ;
 
 #
-# Rule to compile a set of .o files into one .o file
+# Rule to compile a set of .o files into one .a file (without symbol table)
 #
 ifdef builtin-target
-quiet_cmd_link_o_target = AR      $@
-# If the list of objects to link is empty, just create an empty built-in.o
-cmd_link_o_target = $(if $(strip $(obj-y)),\
-		      rm -f $@; $(AR) cDPrsT $@ $(filter $(obj-y), $^), \
-		      rm -f $@; $(AR) cDPrsT$(KBUILD_ARFLAGS) $@)
 
-$(builtin-target): $(obj-y) FORCE
-	$(call if_changed,link_o_target)
+quiet_cmd_ar_builtin = AR      $@
+# Modified for U-Boot, we create thin archives directly, instead of using the kernel script
+# Check f49821ee32b76 and 6358d6e8b98 in kernel
+      cmd_ar_builtin = rm -f $@; $(AR) rcTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)
+
+$(builtin-target): $(real-obj-y) FORCE
+	$(call if_changed,ar_builtin)
 
 targets += $(builtin-target)
 endif # builtin-target
@@ -341,7 +444,7 @@ $(modorder-target): $(subdir-ym) FORCE
 	$(Q)(cat /dev/null; $(modorder-cmds)) > $@
 
 #
-# Rule to compile a set of .o files into one .a file
+# Rule to compile a set of .o files into one .a file (with symbol table)
 #
 ifdef lib-target
 
@@ -349,25 +452,40 @@ $(lib-target): $(lib-y) FORCE
 	$(call if_changed,ar)
 
 targets += $(lib-target)
-endif
 
-quiet_cmd_link_multi-y = AR      $@
-cmd_link_multi-y = rm -f $@; $(AR) cDPrsT$(KBUILD_ARFLAGS) $@ $(filter %.o,$^)
+dummy-object = $(obj)/.lib_exports.o
+ksyms-lds = $(dot-target).lds
+
+quiet_cmd_export_list = EXPORTS $@
+cmd_export_list = $(OBJDUMP) -h $< | \
+	sed -ne '/___ksymtab/s/.*+\([^ ]*\).*/EXTERN(\1)/p' >$(ksyms-lds);\
+	rm -f $(dummy-object);\
+	echo | $(CC) $(a_flags) -c -o $(dummy-object) -x assembler -;\
+	$(LD) $(ld_flags) -r -o $@ -T $(ksyms-lds) $(dummy-object);\
+	rm $(dummy-object) $(ksyms-lds)
+
+$(obj)/lib-ksyms.o: $(lib-target) FORCE
+	$(call if_changed,export_list)
 
-quiet_cmd_link_multi-m = AR [M]  $@
-cmd_link_multi-m = $(cmd_link_multi-y)
+targets += $(obj)/lib-ksyms.o
 
-$(multi-used-y): FORCE
-	$(call if_changed,link_multi-y)
-$(call multi_depend, $(multi-used-y), .o, -objs -y)
+endif
+
+# NOTE:
+# Do not replace $(filter %.o,^) with $(real-prereqs). When a single object
+# module is turned into a multi object module, $^ will contain header file
+# dependencies recorded in the .*.cmd file.
+quiet_cmd_link_multi-m = LD [M]  $@
+cmd_link_multi-m = $(LD) $(ld_flags) -r -o $@ $(filter %.o,$^) $(cmd_secanalysis)
 
 $(multi-used-m): FORCE
 	$(call if_changed,link_multi-m)
-	@{ echo $(@:.o=.ko); echo $(filter %.o,$^); } > $(MODVERDIR)/$(@F:.o=.mod)
-$(call multi_depend, $(multi-used-m), .o, -objs -y)
-
-targets += $(multi-used-y) $(multi-used-m)
+	@{ echo $(@:.o=.ko); echo $(filter %.o,$^); \
+	   $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
+$(call multi_depend, $(multi-used-m), .o, -objs -y -m)
 
+targets += $(multi-used-m)
+targets := $(filter-out $(PHONY), $(targets))
 
 # Add intermediate targets:
 # When building objects with specific suffix patterns, add intermediate
@@ -375,9 +493,13 @@ targets += $(multi-used-y) $(multi-used-m)
 intermediate_targets = $(foreach sfx, $(2), \
 				$(patsubst %$(strip $(1)),%$(sfx), \
 					$(filter %$(strip $(1)), $(targets))))
+# %.asn1.o <- %.asn1.[ch] <- %.asn1
+# %.dtb.o <- %.dtb.S <- %.dtb <- %.dts
 # %.lex.o <- %.lex.c <- %.l
 # %.tab.o <- %.tab.[ch] <- %.y
-targets += $(call intermediate_targets, .lex.o, .lex.c) \
+targets += $(call intermediate_targets, .asn1.o, .asn1.c .asn1.h) \
+	   $(call intermediate_targets, .dtb.o, .dtb.S .dtb) \
+	   $(call intermediate_targets, .lex.o, .lex.c) \
 	   $(call intermediate_targets, .tab.o, .tab.c .tab.h)
 
 # Descending
@@ -385,7 +507,7 @@ targets += $(call intermediate_targets, .lex.o, .lex.c) \
 
 PHONY += $(subdir-ym)
 $(subdir-ym):
-	$(Q)$(MAKE) $(build)=$@
+	$(Q)$(MAKE) $(build)=$@ need-builtin=$(if $(findstring $@,$(subdir-obj-y)),1)
 
 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 # ---------------------------------------------------------------------------
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index f687515fc79..7df62263bc4 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -67,5 +67,14 @@ ifeq ("$(strip $(warning))","")
 endif
 
 KBUILD_CFLAGS += $(warning)
+else
 
+ifdef CONFIG_CC_IS_CLANG
+KBUILD_CFLAGS += $(call cc-disable-warning, initializer-overrides)
+KBUILD_CFLAGS += $(call cc-disable-warning, unused-value)
+KBUILD_CFLAGS += $(call cc-disable-warning, format)
+KBUILD_CFLAGS += $(call cc-disable-warning, sign-compare)
+KBUILD_CFLAGS += $(call cc-disable-warning, format-zero-length)
+KBUILD_CFLAGS += $(call cc-disable-warning, uninitialized)
+endif
 endif
diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins
new file mode 100644
index 00000000000..5f7df50cfe7
--- /dev/null
+++ b/scripts/Makefile.gcc-plugins
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: GPL-2.0
+
+gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY)	+= cyc_complexity_plugin.so
+
+gcc-plugin-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY)	+= latent_entropy_plugin.so
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY)		\
+		+= -DLATENT_ENTROPY_PLUGIN
+ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
+    DISABLE_LATENT_ENTROPY_PLUGIN += -fplugin-arg-latent_entropy_plugin-disable
+endif
+export DISABLE_LATENT_ENTROPY_PLUGIN
+
+gcc-plugin-$(CONFIG_GCC_PLUGIN_SANCOV)		+= sancov_plugin.so
+
+gcc-plugin-$(CONFIG_GCC_PLUGIN_STRUCTLEAK)	+= structleak_plugin.so
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_VERBOSE)	\
+		+= -fplugin-arg-structleak_plugin-verbose
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF)		\
+		+= -fplugin-arg-structleak_plugin-byref
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL)	\
+		+= -fplugin-arg-structleak_plugin-byref-all
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STRUCTLEAK)		\
+		+= -DSTRUCTLEAK_PLUGIN
+
+gcc-plugin-$(CONFIG_GCC_PLUGIN_RANDSTRUCT)	+= randomize_layout_plugin.so
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT)		\
+		+= -DRANDSTRUCT_PLUGIN
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_RANDSTRUCT_PERFORMANCE)	\
+		+= -fplugin-arg-randomize_layout_plugin-performance-mode
+
+gcc-plugin-$(CONFIG_GCC_PLUGIN_STACKLEAK)	+= stackleak_plugin.so
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STACKLEAK)		\
+		+= -DSTACKLEAK_PLUGIN
+gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_STACKLEAK)		\
+		+= -fplugin-arg-stackleak_plugin-track-min-size=$(CONFIG_STACKLEAK_TRACK_MIN_SIZE)
+ifdef CONFIG_GCC_PLUGIN_STACKLEAK
+    DISABLE_STACKLEAK_PLUGIN += -fplugin-arg-stackleak_plugin-disable
+endif
+export DISABLE_STACKLEAK_PLUGIN
+
+gcc-plugin-$(CONFIG_GCC_PLUGIN_ARM_SSP_PER_TASK) += arm_ssp_per_task_plugin.so
+ifdef CONFIG_GCC_PLUGIN_ARM_SSP_PER_TASK
+    DISABLE_ARM_SSP_PER_TASK_PLUGIN += -fplugin-arg-arm_ssp_per_task_plugin-disable
+endif
+export DISABLE_ARM_SSP_PER_TASK_PLUGIN
+
+# All the plugin CFLAGS are collected here in case a build target needs to
+# filter them out of the KBUILD_CFLAGS.
+GCC_PLUGINS_CFLAGS := $(strip $(addprefix -fplugin=$(objtree)/scripts/gcc-plugins/, $(gcc-plugin-y)) $(gcc-plugin-cflags-y))
+# The sancov_plugin.so is included via CFLAGS_KCOV, so it is removed here.
+GCC_PLUGINS_CFLAGS := $(filter-out %/sancov_plugin.so, $(GCC_PLUGINS_CFLAGS))
+export GCC_PLUGINS_CFLAGS
+
+# Add the flags to the build!
+KBUILD_CFLAGS += $(GCC_PLUGINS_CFLAGS)
+
+# All enabled GCC plugins are collected here for building below.
+GCC_PLUGIN := $(gcc-plugin-y)
+export GCC_PLUGIN
diff --git a/scripts/Makefile.kcov b/scripts/Makefile.kcov
new file mode 100644
index 00000000000..3d61c4bfcbe
--- /dev/null
+++ b/scripts/Makefile.kcov
@@ -0,0 +1,9 @@
+ifdef CONFIG_KCOV
+
+kcov-flags-$(CONFIG_CC_HAS_SANCOV_TRACE_PC)	+= -fsanitize-coverage=trace-pc
+kcov-flags-$(CONFIG_KCOV_ENABLE_COMPARISONS)	+= -fsanitize-coverage=trace-cmp
+kcov-flags-$(CONFIG_GCC_PLUGIN_SANCOV)		+= -fplugin=$(objtree)/scripts/gcc-plugins/sancov_plugin.so
+
+export CFLAGS_KCOV := $(kcov-flags-y)
+
+endif
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 19a5be57495..5db2fbc418a 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -5,46 +5,40 @@ ccflags-y  += $(EXTRA_CFLAGS)
 cppflags-y += $(EXTRA_CPPFLAGS)
 ldflags-y  += $(EXTRA_LDFLAGS)
 
-#
-# flags that take effect in sub directories
-export KBUILD_SUBDIR_ASFLAGS := $(KBUILD_SUBDIR_ASFLAGS) $(subdir-asflags-y)
-export KBUILD_SUBDIR_CCFLAGS := $(KBUILD_SUBDIR_CCFLAGS) $(subdir-ccflags-y)
+# flags that take effect in current and sub directories
+KBUILD_AFLAGS += $(subdir-asflags-y)
+KBUILD_CFLAGS += $(subdir-ccflags-y)
 
 # Figure out what we need to build from the various variables
 # ===========================================================================
 
 # When an object is listed to be built compiled-in and modular,
 # only build the compiled-in version
-
 obj-m := $(filter-out $(obj-y),$(obj-m))
 
 # Libraries are always collected in one lib file.
 # Filter out objects already built-in
-
 lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
 
+# Determine modorder.
+# Unfortunately, we don't have information about ordering between -y
+# and -m subdirs.  Just put -y's first.
+modorder	:= $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko))
 
 # Handle objects in subdirs
 # ---------------------------------------------------------------------------
-# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.o
+# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.a
 #   and add the directory to the list of dirs to descend into: $(subdir-y)
 # o if we encounter foo/ in $(obj-m), remove it from $(obj-m)
 #   and add the directory to the list of dirs to descend into: $(subdir-m)
-
-# Determine modorder.
-# Unfortunately, we don't have information about ordering between -y
-# and -m subdirs.  Just put -y's first.
-modorder	:= $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko))
-
 __subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y)))
 subdir-y	+= $(__subdir-y)
 __subdir-m	:= $(patsubst %/,%,$(filter %/, $(obj-m)))
 subdir-m	+= $(__subdir-m)
-obj-y		:= $(patsubst %/, %/built-in.o, $(obj-y))
+obj-y		:= $(patsubst %/, %/built-in.a, $(obj-y))
 obj-m		:= $(filter-out %/, $(obj-m))
 
 # Subdirectories we need to descend into
-
 subdir-ym	:= $(sort $(subdir-y) $(subdir-m))
 
 # Expand $(foo-objs) $(foo-y) etc. by replacing their individuals
@@ -54,9 +48,9 @@ multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -),
 # 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) exists, foo.o is a composite object
+# if $(foo-objs), $(foo-y), or $(foo-m) exists, foo.o is a composite object
 multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))
-multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m))))
+multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))), $(m))))
 multi-used   := $(multi-used-y) $(multi-used-m)
 single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m)))
 
@@ -74,11 +68,22 @@ base-dtb-y := $(foreach m, $(multi-dtb-y), $(firstword $(call suffix-search, $m,
 
 # $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to
 # tell kbuild to descend
-subdir-obj-y := $(filter %/built-in.o, $(obj-y))
+subdir-obj-y := $(filter %/built-in.a, $(obj-y))
 
-# Replace multi-part objects by their individual parts, look at local dir only
-real-objs-y := $(foreach m, $(filter-out $(subdir-obj-y), $(obj-y)), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) $(extra-y)
-real-objs-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m)))
+# Replace multi-part objects by their individual parts,
+# including built-in.a from subdirectories
+real-obj-y := $(foreach m, $(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m)))
+real-obj-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m)))
+
+# DTB
+# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
+extra-y				+= $(dtb-y)
+extra-$(CONFIG_OF_ALL_DTBS)	+= $(dtb-)
+
+ifneq ($(CHECK_DTBS),)
+extra-y += $(patsubst %.dtb,%.dt.yaml, $(dtb-y))
+extra-$(CONFIG_OF_ALL_DTBS) += $(patsubst %.dtb,%.dt.yaml, $(dtb-))
+endif
 
 # Add subdir path
 
@@ -91,8 +96,8 @@ obj-y		:= $(addprefix $(obj)/,$(obj-y))
 obj-m		:= $(addprefix $(obj)/,$(obj-m))
 lib-y		:= $(addprefix $(obj)/,$(lib-y))
 subdir-obj-y	:= $(addprefix $(obj)/,$(subdir-obj-y))
-real-objs-y	:= $(addprefix $(obj)/,$(real-objs-y))
-real-objs-m	:= $(addprefix $(obj)/,$(real-objs-m))
+real-obj-y	:= $(addprefix $(obj)/,$(real-obj-y))
+real-obj-m	:= $(addprefix $(obj)/,$(real-obj-m))
 single-used-m	:= $(addprefix $(obj)/,$(single-used-m))
 multi-used-y	:= $(addprefix $(obj)/,$(multi-used-y))
 multi-used-m	:= $(addprefix $(obj)/,$(multi-used-m))
@@ -102,22 +107,25 @@ 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, all of them are
+# concatenated with a colon separator.
+modname-multi = $(subst $(space),:,$(sort $(foreach m,$(multi-used),\
+		$(if $(filter $*.o, $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$(m:.o=)))))
+
+modname = $(if $(modname-multi),$(modname-multi),$(basetarget))
+
 # These flags are needed for modversions and compiling, so we define them here
-# already
-# $(modname_flags) #defines KBUILD_MODNAME as the name of the module it will
+# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
 # end up in (or would, if it gets compiled in)
-# Note: Files that end up in two or more modules are compiled without the
-#       KBUILD_MODNAME definition. The reason is that any made-up name would
-#       differ in different configs.
 name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote)
 basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
-modname_flags  = $(if $(filter 1,$(words $(modname))),\
-                 -DKBUILD_MODNAME=$(call name-fix,$(modname)))
+modname_flags  = -DKBUILD_MODNAME=$(call name-fix,$(modname))
 
-orig_c_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \
+orig_c_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \
                  $(ccflags-y) $(CFLAGS_$(basetarget).o)
 _c_flags       = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags))
-orig_a_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(KBUILD_SUBDIR_ASFLAGS) \
+orig_a_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \
                  $(asflags-y) $(AFLAGS_$(basetarget).o)
 _a_flags       = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags))
 _cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F))
@@ -140,7 +148,19 @@ endif
 ifeq ($(CONFIG_KASAN),y)
 _c_flags += $(if $(patsubst n%,, \
 		$(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
-		$(CFLAGS_KASAN))
+		$(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
+endif
+
+ifeq ($(CONFIG_UBSAN),y)
+_c_flags += $(if $(patsubst n%,, \
+		$(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
+		$(CFLAGS_UBSAN))
+endif
+
+ifeq ($(CONFIG_KCOV),y)
+_c_flags += $(if $(patsubst n%,, \
+	$(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
+	$(CFLAGS_KCOV))
 endif
 
 __c_flags	= $(_c_flags)
@@ -161,7 +181,6 @@ __a_flags	= $(call flags,_a_flags)
 __cpp_flags     = $(call flags,_cpp_flags)
 endif
 endif
-
 # Modified for U-Boot: LINUXINCLUDE -> UBOOTINCLUDE
 c_flags        = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(UBOOTINCLUDE)     \
 		 $(__c_flags) $(modkern_cflags)                           \
@@ -222,7 +241,6 @@ dtc_cpp_flags  = -Wp,-MD,$(depfile).pre.tmp -nostdinc                    \
 # Finds the multi-part object the current object will be linked into
 modname-multi = $(sort $(foreach m,$(multi-used),\
 		$(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=))))
-
 # Useful for describing the dependency of composite objects
 # Usage:
 #   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
@@ -278,12 +296,13 @@ $(obj)/%: $(src)/%_shipped
 # ---------------------------------------------------------------------------
 
 quiet_cmd_ld = LD      $@
-cmd_ld = $(LD) $(ld_flags) $(filter-out FORCE,$^) -o $@
+      cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
 
 # Archive
 # ---------------------------------------------------------------------------
+
 quiet_cmd_ar = AR      $@
-cmd_ar = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)
+      cmd_ar = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)
 
 # Objcopy
 # ---------------------------------------------------------------------------
@@ -295,10 +314,11 @@ cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
 # ---------------------------------------------------------------------------
 
 quiet_cmd_gzip = GZIP    $@
-cmd_gzip = cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@
+      cmd_gzip = cat $(real-prereqs) | gzip -n -f -9 > $@
 
 # DTC
 # ---------------------------------------------------------------------------
+DTC ?= $(objtree)/scripts/dtc/dtc
 
 # Disable noisy checks by default
 ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
@@ -309,7 +329,6 @@ DTC_FLAGS += -Wno-unit_address_vs_reg \
 	-Wno-graph_child_address \
 	-Wno-simple_bus_reg \
 	-Wno-unique_unit_address \
-	-Wno-simple_bus_reg \
 	-Wno-pci_device_reg
 
 # U-Boot specific disables
@@ -567,20 +586,20 @@ printf "%08x\n" $$dec_size |						\
 )
 
 quiet_cmd_bzip2 = BZIP2   $@
-cmd_bzip2 = { cat $(real-prereqs) | bzip2 -9 && $(size_append); } > $@
+      cmd_bzip2 = { cat $(real-prereqs) | bzip2 -9 && $(size_append); } > $@
 
 # Lzma
 # ---------------------------------------------------------------------------
 
 quiet_cmd_lzma = LZMA    $@
-cmd_lzma = { cat $(real-prereqs) | lzma -9 && $(size_append); } > $@
+      cmd_lzma = { cat $(real-prereqs) | lzma -9 && $(size_append); } > $@
 
 quiet_cmd_lzo = LZO     $@
-cmd_lzo = { cat $(real-prereqs) | lzop -9 && $(size_append); } > $@
+      cmd_lzo = { cat $(real-prereqs) | lzop -9 && $(size_append); } > $@
 
 quiet_cmd_lz4 = LZ4     $@
-cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout && \
-	$(size_append); } > $@
+      cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout && \
+                  $(size_append); } > $@
 
 # U-Boot mkimage
 # ---------------------------------------------------------------------------
@@ -702,12 +721,15 @@ quiet_cmd_fdt_rm_props = FDTGREP $@
 # ---------------------------------------------------------------------------
 
 # Default sed regexp - multiline due to syntax constraints
+#
+# Use [:space:] because LLVM's integrated assembler inserts <tab> around
+# the .ascii directive whereas GCC keeps the <space> as-is.
 define sed-offsets
-	"s:[[:space:]]*\.ascii[[:space:]]*\"\(.*\)\":\1:; \
+	's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
 	/^->/{s:->#\(.*\):/* \1 */:; \
 	s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
 	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
-	s:->::; p;}"
+	s:->::; p;}'
 endef
 
 # Use filechk to avoid rebuilds when a header changes, but the resulting file
diff --git a/scripts/Makefile.xpl b/scripts/Makefile.xpl
index 43f27874f9f..03a2f151d91 100644
--- a/scripts/Makefile.xpl
+++ b/scripts/Makefile.xpl
@@ -135,7 +135,7 @@ head-y		:= $(addprefix $(obj)/,$(head-y))
 libs-y		:= $(addprefix $(obj)/,$(libs-y))
 u-boot-spl-dirs	:= $(patsubst %/,%,$(filter %/, $(libs-y)))
 
-libs-y := $(patsubst %/, %/built-in.o, $(libs-y))
+libs-y := $(patsubst %/, %/built-in.a, $(libs-y))
 
 # Add GCC lib
 ifeq ($(CONFIG_USE_PRIVATE_LIBGCC),y)