Merge tag 'kbuild-fixes-v5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Move -Wcast-align to W=3, which tends to be false-positive and there
   is no tree-wide solution.

 - Pass -fmacro-prefix-map to KBUILD_CPPFLAGS because it is a
   preprocessor option and makes sense for .S files as well.

 - Disable -gdwarf-2 for Clang's integrated assembler to avoid warnings.

 - Disable --orphan-handling=warn for LLD 10.0.1 to avoid warnings.

 - Fix undesirable line breaks in *.mod files.

* tag 'kbuild-fixes-v5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: avoid split lines in .mod files
  kbuild: Disable CONFIG_LD_ORPHAN_WARN for ld.lld 10.0.1
  kbuild: Hoist '--orphan-handling' into Kconfig
  Kbuild: do not emit debug info for assembly with LLVM_IAS=1
  kbuild: use -fmacro-prefix-map for .S sources
  Makefile.extrawarn: move -Wcast-align to W=3

3 files changed, 25 insertions, 9 deletions

diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index ae647379b579..4c058f12dd73 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -252,6 +252,9 @@ objtool_dep = $(objtool_obj)					\
 ifdef CONFIG_TRIM_UNUSED_KSYMS
 cmd_gen_ksymdeps = \
 	$(CONFIG_SHELL) $(srctree)/scripts/gen_ksymdeps.sh $@ >> $(dot-target).cmd
+
+# List module undefined symbols
+undefined_syms = $(NM) $< | $(AWK) '$$1 == "U" { printf("%s%s", x++ ? " " : "", $$2) }';
 endif
 
 define rule_cc_o_c
@@ -271,13 +274,6 @@ 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) $(objtool_dep) FORCE
 	$(call if_changed_rule,cc_o_c)
@@ -285,7 +281,7 @@ $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
 
 cmd_mod = { \
 	echo $(if $($*-objs)$($*-y)$($*-m), $(addprefix $(obj)/, $($*-objs) $($*-y) $($*-m)), $(@:.mod=.o)); \
-	$(cmd_undef_syms); \
+	$(undefined_syms) echo; \
 	} > $@
 
 $(obj)/%.mod: $(obj)/%.o FORCE
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 95e4cdb94fe9..6baee1200615 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -60,7 +60,6 @@ endif
 #
 ifneq ($(findstring 2, $(KBUILD_EXTRA_WARN)),)
 
-KBUILD_CFLAGS += -Wcast-align
 KBUILD_CFLAGS += -Wdisabled-optimization
 KBUILD_CFLAGS += -Wnested-externs
 KBUILD_CFLAGS += -Wshadow
@@ -80,6 +79,7 @@ endif
 ifneq ($(findstring 3, $(KBUILD_EXTRA_WARN)),)
 
 KBUILD_CFLAGS += -Wbad-function-cast
+KBUILD_CFLAGS += -Wcast-align
 KBUILD_CFLAGS += -Wcast-qual
 KBUILD_CFLAGS += -Wconversion
 KBUILD_CFLAGS += -Wpacked
diff --git a/scripts/lld-version.sh b/scripts/lld-version.sh
new file mode 100755
index 000000000000..d70edb4d8a4f
--- /dev/null
+++ b/scripts/lld-version.sh
@@ -0,0 +1,20 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Usage: $ ./scripts/lld-version.sh ld.lld
+#
+# Print the linker version of `ld.lld' in a 5 or 6-digit form
+# such as `100001' for ld.lld 10.0.1 etc.
+
+linker_string="$($* --version)"
+
+if ! ( echo $linker_string | grep -q LLD ); then
+	echo 0
+	exit 1
+fi
+
+VERSION=$(echo $linker_string | cut -d ' ' -f 2)
+MAJOR=$(echo $VERSION | cut -d . -f 1)
+MINOR=$(echo $VERSION | cut -d . -f 2)
+PATCHLEVEL=$(echo $VERSION | cut -d . -f 3)
+printf "%d%02d%02d\\n" $MAJOR $MINOR $PATCHLEVEL