Merge tag 'kbuild-fixes-v5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

- fix documents

- fix warning in 'make localmodconfig'

* tag 'kbuild-fixes-v5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: remove redundant assignment prompt = prompt
kbuild: Documentation: clean up makefiles.rst
kconfig: streamline_config.pl: check defined(ENV variable) before using it
Documentation/llvm: Improve formatting of commands, variables, and arguments

Documentation/kbuild/llvm.rst

···
 Clang
 -----
 
-The compiler used can be swapped out via `CC=` command line argument to `make`.
-`CC=` should be set when selecting a config and during a build.
+The compiler used can be swapped out via ``CC=`` command line argument to ``make``.
+``CC=`` should be set when selecting a config and during a build. ::
 
 	make CC=clang defconfig
 
···
 ---------------
 
 A single Clang compiler binary will typically contain all supported backends,
-which can help simplify cross compiling.
+which can help simplify cross compiling. ::
 
 	ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- make CC=clang
 
-`CROSS_COMPILE` is not used to prefix the Clang compiler binary, instead
-`CROSS_COMPILE` is used to set a command line flag: `--target <triple>`. For
-example:
+``CROSS_COMPILE`` is not used to prefix the Clang compiler binary, instead
+``CROSS_COMPILE`` is used to set a command line flag: ``--target <triple>``. For
+example: ::
 
 	clang --target aarch64-linux-gnu foo.c
 
 LLVM Utilities
 --------------
 
-LLVM has substitutes for GNU binutils utilities. Kbuild supports `LLVM=1`
-to enable them.
+LLVM has substitutes for GNU binutils utilities. Kbuild supports ``LLVM=1``
+to enable them. ::
 
 	make LLVM=1
 
-They can be enabled individually. The full list of the parameters:
+They can be enabled individually. The full list of the parameters: ::
 
-	make CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \\
-	  OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-size \\
-	  READELF=llvm-readelf HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar \\
+	make CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \
+	  OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-size \
+	  READELF=llvm-readelf HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar \
 	  HOSTLD=ld.lld
 
 Currently, the integrated assembler is disabled by default. You can pass
-`LLVM_IAS=1` to enable it.
+``LLVM_IAS=1`` to enable it.
 
 Getting Help
 ------------

Documentation/kbuild/makefiles.rst

···
 	   --- 3.5 Library file goals - lib-y
 	   --- 3.6 Descending down in directories
 	   --- 3.7 Compilation flags
-	   --- 3.8 Command line dependency
+	   --- 3.8 <deleted>
 	   --- 3.9 Dependency tracking
 	   --- 3.10 Special Rules
 	   --- 3.11 $(CC) support functions
···
 
 	=== 7 Architecture Makefiles
 	   --- 7.1 Set variables to tweak the build to the architecture
-	   --- 7.2 Add prerequisites to archheaders:
-	   --- 7.3 Add prerequisites to archprepare:
+	   --- 7.2 Add prerequisites to archheaders
+	   --- 7.3 Add prerequisites to archprepare
 	   --- 7.4 List directories to visit when descending
 	   --- 7.5 Architecture-specific boot images
 	   --- 7.6 Building non-kbuild targets
···
 be used and if both a 'Makefile' and a 'Kbuild' file exists, then the 'Kbuild'
 file will be used.
 
-Section 3.1 "Goal definitions" is a quick intro, further chapters provide
+Section 3.1 "Goal definitions" is a quick intro; further chapters provide
 more details, with real examples.
 
 3.1 Goal definitions
···
 		KBUILD_LDFLAGS         := -m elf_s390
 
 	Note: ldflags-y can be used to further customise
-	the flags used. See chapter 3.7.
+	the flags used. See section 3.7.
 
     LDFLAGS_vmlinux
 	Options for $(LD) when linking vmlinux
···
 
 	In this example, the file target maketools will be processed
 	before descending down in the subdirectories.
-	See also chapter XXX-TODO that describe how kbuild supports
+	See also chapter XXX-TODO that describes how kbuild supports
 	generating offset header files.
 
 
···
 	always be built.
 	Assignments to $(targets) are without $(obj)/ prefix.
 	if_changed may be used in conjunction with custom commands as
-	defined in 6.8 "Custom kbuild commands".
+	defined in 7.8 "Custom kbuild commands".
 
 	Note: It is a typical mistake to forget the FORCE prerequisite.
 	Another common pitfall is that whitespace is sometimes
···
 	that may be shared between individual architectures.
 	The recommended approach how to use a generic header file is
 	to list the file in the Kbuild file.
-	See "7.2 generic-y" for further info on syntax etc.
+	See "8.2 generic-y" for further info on syntax etc.
 
 7.11 Post-link pass
 -------------------
···
 
 - Describe how kbuild supports shipped files with _shipped.
 - Generating offset header files.
-- Add more variables to section 7?
+- Add more variables to chapters 7 or 9?

scripts/kconfig/nconf.c

···
 			switch (ptype) {
 			case P_MENU:
 				child_count++;
-				prompt = prompt;
 				if (single_menu_mode) {
 					item_make(menu, 'm',
 						"%s%*c%s",

scripts/kconfig/streamline_config.pl

···
 }
 
 my %setconfigs;
-my @preserved_kconfigs = split(/:/,$ENV{LMC_KEEP});
+my @preserved_kconfigs;
+if (defined($ENV{'LMC_KEEP'})) {
+	@preserved_kconfigs = split(/:/,$ENV{LMC_KEEP});
+}
 
 sub in_preserved_kconfigs {
     my $kconfig = $config2kfile{$_[0]};