Kbuild updates for v6.19

- Enable -fms-extensions, allowing anonymous use of tagged struct or
     union in struct/union (tag kbuild-ms-extensions-6.19).  An exemplary
     conversion patch is added here, too (btrfs).
 
   - Introduce architecture-specific CC_CAN_LINK and flags for userprogs
 
   - Add new packaging target 'modules-cpio-pkg' for building a initramfs
     cpio w/ kmods
 
   - Handle included .c files in gen_compile_commands
 
   - Minor kbuild changes:
     - Use objtree for module signing key path, fixing oot kmod signing
     - Improve documentation of KBUILD_BUILD_TIMESTAMP
     - Reuse KBUILD_USERCFLAGS for UAPI, instead of defining twice
     - Rename scripts/Makefile.extrawarn to Makefile.warn
     - Drop obsolete types.h check from headers_check.pl
     - Remove outdated config leak ignore entries
 
 Signed-off-by: Nicolas Schier <nsc@kernel.org>
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Merge tag 'kbuild-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux

Pull Kbuild updates from Nicolas Schier:

  - Enable -fms-extensions, allowing anonymous use of tagged struct or
    union in struct/union (tag kbuild-ms-extensions-6.19). An exemplary
    conversion patch is added here, too (btrfs).

    [ Editor's note: the core of this actually came in early through a
      shared branch and a few other trees    - Linus ]

  - Introduce architecture-specific CC_CAN_LINK and flags for userprogs

  - Add new packaging target 'modules-cpio-pkg' for building a initramfs
    cpio w/ kmods

  - Handle included .c files in gen_compile_commands

  - Minor kbuild changes:
     - Use objtree for module signing key path, fixing oot kmod signing
     - Improve documentation of KBUILD_BUILD_TIMESTAMP
     - Reuse KBUILD_USERCFLAGS for UAPI, instead of defining twice
     - Rename scripts/Makefile.extrawarn to Makefile.warn
     - Drop obsolete types.h check from headers_check.pl
     - Remove outdated config leak ignore entries

* tag 'kbuild-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
  kbuild: add target to build a cpio containing modules
  initramfs: add gen_init_cpio to hostprogs unconditionally
  kbuild: allow architectures to override CC_CAN_LINK
  init: deduplicate cc-can-link.sh invocations
  kbuild: don't enable CC_CAN_LINK if the dummy program generates warnings
  scripts: headers_install.sh: Remove two outdated config leak ignore entries
  scripts/clang-tools: Handle included .c files in gen_compile_commands
  kbuild: uapi: Drop types.h check from headers_check.pl
  kbuild: Rename Makefile.extrawarn to Makefile.warn
  MAINTAINERS, .mailmap: Update mail address for Nicolas Schier
  kbuild: uapi: reuse KBUILD_USERCFLAGS
  kbuild: doc: improve KBUILD_BUILD_TIMESTAMP documentation
  kbuild: Use objtree for module signing key path
  btrfs: send: make use of -fms-extensions for defining struct fs_path

.mailmap

@@ -589,8 +589,8 @@ Nicolas Pitre <nico@fluxnic.net> <nicolas.pitre@linaro.org>
 Nicolas Pitre <nico@fluxnic.net> <nico@linaro.org>
 Nicolas Saenz Julienne <nsaenz@kernel.org> <nsaenzjulienne@suse.de>
 Nicolas Saenz Julienne <nsaenz@kernel.org> <nsaenzjulienne@suse.com>
-Nicolas Schier <nicolas.schier@linux.dev> <n.schier@avm.de>
+Nicolas Schier <nsc@kernel.org> <n.schier@avm.de>
-Nicolas Schier <nicolas.schier@linux.dev> <nicolas@fjasle.eu>
+Nicolas Schier <nsc@kernel.org> <nicolas@fjasle.eu>
 Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
 Nikolay Aleksandrov <razor@blackwall.org> <naleksan@redhat.com>
 Nikolay Aleksandrov <razor@blackwall.org> <nikolay@redhat.com>

Documentation/kbuild/kbuild.rst

@@ -328,8 +328,14 @@ KBUILD_BUILD_TIMESTAMP
 ----------------------
 Setting this to a date string overrides the timestamp used in the
 UTS_VERSION definition (uname -v in the running kernel). The value has to
-be a string that can be passed to date -d. The default value
+be a string that can be passed to date -d. E.g.::
-is the output of the date command at one point during build.
+
+    $ KBUILD_BUILD_TIMESTAMP="Mon Oct 13 00:00:00 UTC 2025" make
+
+The default value is the output of the date command at one point during
+build. If provided, this timestamp will also be used for mtime fields
+within any initramfs archive. Initramfs mtimes are 32-bit, so dates before
+the 1970 Unix epoch, or after 2106-02-07 06:28:15 UTC will fail.
 
 KBUILD_BUILD_USER, KBUILD_BUILD_HOST
 ------------------------------------

MAINTAINERS

@@ -13498,7 +13498,7 @@ F:	fs/autofs/
 
 KERNEL BUILD + files below scripts/ (unless maintained elsewhere)
 M:	Nathan Chancellor <nathan@kernel.org>
-M:	Nicolas Schier <nicolas@fjasle.eu>
+M:	Nicolas Schier <nsc@kernel.org>
 L:	linux-kbuild@vger.kernel.org
 S:	Odd Fixes
 Q:	https://patchwork.kernel.org/project/linux-kbuild/list/

Makefile

@@ -1084,7 +1084,7 @@ KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srcroot)/=)
 endif
 
 # include additional Makefiles when needed
-include-y			:= scripts/Makefile.extrawarn
+include-y			:= scripts/Makefile.warn
 include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
 include-$(CONFIG_DEBUG_INFO_BTF)+= scripts/Makefile.btf
 include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
@@ -1137,8 +1137,17 @@ ifneq ($(CONFIG_ARCH_VMLINUX_NEEDS_RELOCS),)
 LDFLAGS_vmlinux	+= --emit-relocs --discard-none
 endif
 
-# Align the bit size of userspace programs with the kernel
+# Align the architecture of userspace programs with the kernel
-USERFLAGS_FROM_KERNEL := -m32 -m64 --target=%
+USERFLAGS_FROM_KERNEL := --target=%
+
+ifdef CONFIG_ARCH_USERFLAGS
+KBUILD_USERCFLAGS += $(CONFIG_ARCH_USERFLAGS)
+KBUILD_USERLDFLAGS += $(CONFIG_ARCH_USERFLAGS)
+else
+# If not overridden also inherit the bit size
+USERFLAGS_FROM_KERNEL += -m32 -m64
+endif
+
 KBUILD_USERCFLAGS  += $(filter $(USERFLAGS_FROM_KERNEL), $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
 KBUILD_USERLDFLAGS += $(filter $(USERFLAGS_FROM_KERNEL), $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
 

drivers/gpu/drm/Makefile

@@ -6,7 +6,7 @@
 CFLAGS-$(CONFIG_DRM_USE_DYNAMIC_DEBUG)	+= -DDYNAMIC_DEBUG_MODULE
 
 # Unconditionally enable W=1 warnings locally
-# --- begin copy-paste W=1 warnings from scripts/Makefile.extrawarn
+# --- begin copy-paste W=1 warnings from scripts/Makefile.warn
 subdir-ccflags-y += -Wextra -Wunused -Wno-unused-parameter
 subdir-ccflags-y += $(call cc-option, -Wrestrict)
 subdir-ccflags-y += -Wmissing-format-attribute

fs/btrfs/send.c

@@ -47,28 +47,30 @@
  * It allows fast adding of path elements on the right side (normal path) and
  * fast adding to the left side (reversed path). A reversed path can also be
  * unreversed if needed.
+ *
+ * The definition of struct fs_path relies on -fms-extensions to allow
+ * including a tagged struct as an anonymous member.
  */
-struct fs_path {
+struct __fs_path {
-	union {
+	char *start;
-		struct {
+	char *end;
-			char *start;
-			char *end;
 
-			char *buf;
+	char *buf;
-			unsigned short buf_len:15;
+	unsigned short buf_len:15;
-			unsigned short reversed:1;
+	unsigned short reversed:1;
-			char inline_buf[];
+};
-		};
+static_assert(sizeof(struct __fs_path) < 256);
-		/*
+struct fs_path {
-		 * Average path length does not exceed 200 bytes, we'll have
+	struct __fs_path;
-		 * better packing in the slab and higher chance to satisfy
+	/*
-		 * an allocation later during send.
+	 * Average path length does not exceed 200 bytes, we'll have
-		 */
+	 * better packing in the slab and higher chance to satisfy
-		char pad[256];
+	 * an allocation later during send.
-	};
+	 */
+	char inline_buf[256 - sizeof(struct __fs_path)];
 };
 #define FS_PATH_INLINE_SIZE \
-	(sizeof(struct fs_path) - offsetof(struct fs_path, inline_buf))
+	sizeof_field(struct fs_path, inline_buf)
 
 
 /* reused for each extent */
@@ -305,7 +307,6 @@ struct send_ctx {
 	struct btrfs_lru_cache dir_created_cache;
 	struct btrfs_lru_cache dir_utimes_cache;
 
-	/* Must be last as it ends in a flexible-array member. */
 	struct fs_path cur_inode_path;
 };
 

init/Kconfig

@@ -82,10 +82,14 @@ config RUSTC_LLVM_VERSION
 	int
 	default $(rustc-llvm-version)
 
+config ARCH_HAS_CC_CAN_LINK
+	bool
+
 config CC_CAN_LINK
 	bool
-	default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLAGS) $(m64-flag)) if 64BIT
+	default ARCH_CC_CAN_LINK if ARCH_HAS_CC_CAN_LINK
-	default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLAGS) $(m32-flag))
+	default $(cc_can_link_user,$(m64-flag)) if 64BIT
+	default $(cc_can_link_user,$(m32-flag))
 
 # Fixed in GCC 14, 13.3, 12.4 and 11.5
 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113921

scripts/Kconfig.include

@@ -65,6 +65,9 @@ cc-option-bit = $(if-success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null,$
 m32-flag := $(cc-option-bit,-m32)
 m64-flag := $(cc-option-bit,-m64)
 
+# Test whether the compiler can link userspace applications
+cc_can_link_user = $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLAGS) $(1))
+
 rustc-version := $(shell,$(srctree)/scripts/rustc-version.sh $(RUSTC))
 rustc-llvm-version := $(shell,$(srctree)/scripts/rustc-llvm-version.sh $(RUSTC))
 

scripts/Makefile.modinst

@@ -100,7 +100,7 @@ endif
 # Don't stop modules_install even if we can't sign external modules.
 #
 ifeq ($(filter pkcs11:%, $(CONFIG_MODULE_SIG_KEY)),)
-sig-key := $(if $(wildcard $(CONFIG_MODULE_SIG_KEY)),,$(srctree)/)$(CONFIG_MODULE_SIG_KEY)
+sig-key := $(if $(wildcard $(CONFIG_MODULE_SIG_KEY)),,$(objtree)/)$(CONFIG_MODULE_SIG_KEY)
 else
 sig-key := $(CONFIG_MODULE_SIG_KEY)
 endif

scripts/Makefile.package

@@ -189,6 +189,25 @@ tar-pkg: linux-$(KERNELRELEASE)-$(ARCH).tar
 tar%-pkg: linux-$(KERNELRELEASE)-$(ARCH).tar.% FORCE
 	@:
 
+# modules-cpio-pkg - generate an initramfs with the modules
+# ---------------------------------------------------------------------------
+
+.tmp_modules_cpio: FORCE
+	$(Q)$(MAKE) -f $(srctree)/Makefile
+	$(Q)rm -rf $@
+	$(Q)$(MAKE) -f $(srctree)/Makefile INSTALL_MOD_PATH=$@ modules_install
+
+quiet_cmd_cpio = CPIO    $@
+      cmd_cpio = $(CONFIG_SHELL) $(srctree)/usr/gen_initramfs.sh -o $@ $<
+
+modules-$(KERNELRELEASE)-$(ARCH).cpio: .tmp_modules_cpio
+	$(Q)$(MAKE) $(build)=usr usr/gen_init_cpio
+	$(call cmd,cpio)
+
+PHONY += modules-cpio-pkg
+modules-cpio-pkg: modules-$(KERNELRELEASE)-$(ARCH).cpio
+	@:
+
 # perf-tar*-src-pkg - generate a source tarball with perf source
 # ---------------------------------------------------------------------------
 
@@ -245,6 +264,7 @@ help:
 	@echo '  tarbz2-pkg          - Build the kernel as a bzip2 compressed tarball'
 	@echo '  tarxz-pkg           - Build the kernel as a xz compressed tarball'
 	@echo '  tarzst-pkg          - Build the kernel as a zstd compressed tarball'
+	@echo '  modules-cpio-pkg    - Build the kernel modules as cpio archive'
 	@echo '  perf-tar-src-pkg    - Build the perf source tarball with no compression'
 	@echo '  perf-targz-src-pkg  - Build the perf source tarball with gzip compression'
 	@echo '  perf-tarbz2-src-pkg - Build the perf source tarball with bz2 compression'

scripts/cc-can-link.sh

@@ -1,7 +1,7 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 
-cat << "END" | $@ -x c - -o /dev/null >/dev/null 2>&1
+cat << "END" | $@ -Werror -Wl,--fatal-warnings -x c - -o /dev/null >/dev/null 2>&1
 #include <stdio.h>
 int main(void)
 {

scripts/clang-tools/gen_compile_commands.py

@@ -21,6 +21,12 @@ _DEFAULT_LOG_LEVEL = 'WARNING'
 _FILENAME_PATTERN = r'^\..*\.cmd$'
 _LINE_PATTERN = r'^(saved)?cmd_[^ ]*\.o := (?P<command_prefix>.* )(?P<file_path>[^ ]*\.[cS]) *(;|$)'
 _VALID_LOG_LEVELS = ['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL']
+
+# Pre-compiled regexes for better performance
+_INCLUDE_PATTERN = re.compile(r'^\s*#\s*include\s*[<"]([^>"]*)[>"]')
+_C_INCLUDE_PATTERN = re.compile(r'^\s*#\s*include\s*"([^"]*\.c)"\s*$')
+_FILENAME_MATCHER = re.compile(_FILENAME_PATTERN)
+
 # The tools/ directory adopts a different build system, and produces .cmd
 # files in a different format. Do not support it.
 _EXCLUDE_DIRS = ['.git', 'Documentation', 'include', 'tools']
@@ -82,7 +88,6 @@ def cmdfiles_in_dir(directory):
         The path to a .cmd file.
     """
 
-    filename_matcher = re.compile(_FILENAME_PATTERN)
     exclude_dirs = [ os.path.join(directory, d) for d in _EXCLUDE_DIRS ]
 
     for dirpath, dirnames, filenames in os.walk(directory, topdown=True):
@@ -92,7 +97,7 @@ def cmdfiles_in_dir(directory):
             continue
 
         for filename in filenames:
-            if filename_matcher.match(filename):
+            if _FILENAME_MATCHER.match(filename):
                 yield os.path.join(dirpath, filename)
 
 
@@ -149,8 +154,87 @@ def cmdfiles_for_modorder(modorder):
                     yield to_cmdfile(mod_line.rstrip())
 
 
+def extract_includes_from_file(source_file, root_directory):
+    """Extract #include statements from a C file.
+
+    Args:
+        source_file: Path to the source .c file to analyze
+        root_directory: Root directory for resolving relative paths
+
+    Returns:
+        List of header files that should be included (without quotes/brackets)
+    """
+    includes = []
+    if not os.path.exists(source_file):
+        return includes
+
+    try:
+        with open(source_file, 'r') as f:
+            for line in f:
+                line = line.strip()
+                # Look for #include statements.
+                # Match both #include "header.h" and #include <header.h>.
+                match = _INCLUDE_PATTERN.match(line)
+                if match:
+                    header = match.group(1)
+                    # Skip including other .c files to avoid circular includes.
+                    if not header.endswith('.c'):
+                        # For relative includes (quoted), resolve path relative to source file.
+                        if '"' in line:
+                            src_dir = os.path.dirname(source_file)
+                            header_path = os.path.join(src_dir, header)
+                            if os.path.exists(header_path):
+                                rel_header = os.path.relpath(header_path, root_directory)
+                                includes.append(rel_header)
+                            else:
+                                includes.append(header)
+                        else:
+                            # System include like <linux/sched.h>.
+                            includes.append(header)
+    except IOError:
+        pass
+
+    return includes
+
+
+def find_included_c_files(source_file, root_directory):
+    """Find .c files that are included by the given source file.
+
+    Args:
+        source_file: Path to the source .c file
+        root_directory: Root directory for resolving relative paths
+
+    Yields:
+        Full paths to included .c files
+    """
+    if not os.path.exists(source_file):
+        return
+
+    try:
+        with open(source_file, 'r') as f:
+            for line in f:
+                line = line.strip()
+                # Look for #include "*.c" patterns.
+                match = _C_INCLUDE_PATTERN.match(line)
+                if match:
+                    included_file = match.group(1)
+                    # Handle relative paths.
+                    if not os.path.isabs(included_file):
+                        src_dir = os.path.dirname(source_file)
+                        included_file = os.path.join(src_dir, included_file)
+
+                    # Normalize the path.
+                    included_file = os.path.normpath(included_file)
+
+                    # Check if the file exists.
+                    if os.path.exists(included_file):
+                        yield included_file
+    except IOError:
+        pass
+
+
 def process_line(root_directory, command_prefix, file_path):
-    """Extracts information from a .cmd line and creates an entry from it.
+    """Extracts information from a .cmd line and creates entries from it.
 
     Args:
         root_directory: The directory that was searched for .cmd files. Usually
@@ -160,7 +244,8 @@ def process_line(root_directory, command_prefix, file_path):
             Usually relative to root_directory, but sometimes absolute.
 
     Returns:
-        An entry to append to compile_commands.
+        A list of entries to append to compile_commands (may include multiple
+        entries if the source file includes other .c files).
 
     Raises:
         ValueError: Could not find the extracted file based on file_path and
@@ -176,11 +261,47 @@ def process_line(root_directory, command_prefix, file_path):
     abs_path = os.path.realpath(os.path.join(root_directory, file_path))
     if not os.path.exists(abs_path):
         raise ValueError('File %s not found' % abs_path)
-    return {
+
+    entries = []
+
+    # Create entry for the main source file.
+    main_entry = {
         'directory': root_directory,
         'file': abs_path,
         'command': prefix + file_path,
     }
+    entries.append(main_entry)
+
+    # Find and create entries for included .c files.
+    for included_c_file in find_included_c_files(abs_path, root_directory):
+        # For included .c files, create a compilation command that:
+        # 1. Uses the same compilation flags as the parent file
+        # 2. But compiles the included file directly (not the parent)
+        # 3. Includes necessary headers from the parent file for proper macro resolution
+
+        # Convert absolute path to relative for the command.
+        rel_path = os.path.relpath(included_c_file, root_directory)
+
+        # Extract includes from the parent file to provide proper compilation context.
+        extra_includes = ''
+        try:
+            parent_includes = extract_includes_from_file(abs_path, root_directory)
+            if parent_includes:
+                extra_includes = ' ' + ' '.join('-include ' + inc for inc in parent_includes)
+        except IOError:
+            pass
+
+        included_entry = {
+            'directory': root_directory,
+            'file': included_c_file,
+            # Use the same compilation prefix but target the included file directly.
+            # Add extra headers for proper macro resolution.
+            'command': prefix + extra_includes + ' ' + rel_path,
+        }
+        entries.append(included_entry)
+        logging.debug('Added entry for included file: %s', included_c_file)
+
+    return entries
 
 
 def main():
@@ -213,9 +334,9 @@ def main():
                 result = line_matcher.match(f.readline())
                 if result:
                     try:
-                        entry = process_line(directory, result.group('command_prefix'),
+                        entries = process_line(directory, result.group('command_prefix'),
                                              result.group('file_path'))
-                        compile_commands.append(entry)
+                        compile_commands.extend(entries)
                     except ValueError as err:
                         logging.info('Could not add line from %s: %s',
                                      cmdfile, err)

scripts/headers_install.sh

@@ -70,8 +70,6 @@ configs=$(sed -e '
 #
 # The format is <file-name>:<CONFIG-option> in each line.
 config_leak_ignores="
-arch/arc/include/uapi/asm/page.h:CONFIG_ARC_PAGE_SIZE_16K
-arch/arc/include/uapi/asm/page.h:CONFIG_ARC_PAGE_SIZE_4K
 arch/arc/include/uapi/asm/swab.h:CONFIG_ARC_HAS_SWAPE
 arch/arm/include/uapi/asm/ptrace.h:CONFIG_CPU_ENDIAN_BE8
 arch/nios2/include/uapi/asm/swab.h:CONFIG_NIOS2_CI_SWAB_NO

usr/Makefile

@@ -16,6 +16,8 @@ obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
 
 $(obj)/initramfs_data.o: $(obj)/initramfs_inc_data
 
+hostprogs := gen_init_cpio
+
 ramfs-input := $(CONFIG_INITRAMFS_SOURCE)
 cpio-data :=
 
@@ -48,8 +50,6 @@ ifeq ($(cpio-data),)
 
 cpio-data := $(obj)/initramfs_data.cpio
 
-hostprogs := gen_init_cpio
-
 # .initramfs_data.cpio.d is used to identify all files included
 # in initramfs and to detect if any files are added/removed.
 # Removed files are identified by directory timestamp being updated

usr/include/Makefile

@@ -6,16 +6,9 @@
 #
 # -std=c90 (equivalent to -ansi) catches the violation of those.
 # We cannot go as far as adding -Wpedantic since it emits too many warnings.
-UAPI_CFLAGS := -std=c90 -Wall -Werror=implicit-function-declaration
+UAPI_CFLAGS := -std=c90 -Werror=implicit-function-declaration
 
-# In theory, we do not care -m32 or -m64 for header compile tests.
+override c_flags = $(KBUILD_USERCFLAGS) $(UAPI_CFLAGS) -Wp,-MMD,$(depfile) -I $(obj) -I $(srctree)/usr/dummy-include
-# It is here just because CONFIG_CC_CAN_LINK is tested with -m32 or -m64.
-UAPI_CFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS))
-
-# USERCFLAGS might contain sysroot location for CC.
-UAPI_CFLAGS += $(USERCFLAGS)
-
-override c_flags = $(UAPI_CFLAGS) -Wp,-MMD,$(depfile) -I $(obj) -I $(srctree)/usr/dummy-include
 
 # The following are excluded for now because they fail to build.
 #

usr/include/headers_check.pl

@@ -39,7 +39,6 @@ foreach my $file (@files) {
 		$lineno++;
 		&check_include();
 		&check_asm_types();
-		&check_sizetypes();
 		&check_declarations();
 		# Dropped for now. Too much noise &check_config();
 	}
@@ -103,65 +102,3 @@ sub check_asm_types
 		$ret = 1;
 	}
 }
-
-my $linux_types;
-my %import_stack = ();
-sub check_include_typesh
-{
-	my $path = $_[0];
-	my $import_path;
-
-	my $fh;
-	my @file_paths = ($path, $dir . "/" .  $path, dirname($filename) . "/" . $path);
-	for my $possible ( @file_paths ) {
-	    if (not $import_stack{$possible} and open($fh, '<', $possible)) {
-		$import_path = $possible;
-		$import_stack{$import_path} = 1;
-		last;
-	    }
-	}
-	if (eof $fh) {
-	    return;
-	}
-
-	my $line;
-	while ($line = <$fh>) {
-		if ($line =~ m/^\s*#\s*include\s+<linux\/types.h>/) {
-			$linux_types = 1;
-			last;
-		}
-		if (my $included = ($line =~ /^\s*#\s*include\s+[<"](\S+)[>"]/)[0]) {
-			check_include_typesh($included);
-		}
-	}
-	close $fh;
-	delete $import_stack{$import_path};
-}
-
-sub check_sizetypes
-{
-	if ($filename =~ /types.h|int-l64.h|int-ll64.h/o) {
-		return;
-	}
-	if ($lineno == 1) {
-		$linux_types = 0;
-	} elsif ($linux_types >= 1) {
-		return;
-	}
-	if ($line =~ m/^\s*#\s*include\s+<linux\/types.h>/) {
-		$linux_types = 1;
-		return;
-	}
-	if (my $included = ($line =~ /^\s*#\s*include\s+[<"](\S+)[>"]/)[0]) {
-		check_include_typesh($included);
-	}
-	# strip single-line comments, as types may be referenced within them
-	$line =~ s@/\*.*?\*/@@;
-	if ($line =~ m/__[us](8|16|32|64)\b/) {
-		printf STDERR "$filename:$lineno: " .
-		              "found __[us]{8,16,32,64} type " .
-		              "without #include <linux/types.h>\n";
-		$linux_types = 2;
-		$ret = 1;
-	}
-}