Commit a778f5d4 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Daniel Borkmann
Browse files

tools/headers: Pull in stddef.h to uapi to fix BPF selftests build in CI 

With recent sync of linux/in.h tools/include headers are now relying on
__DECLARE_FLEX_ARRAY macro, which isn't itself defined inside
tools/include headers anywhere and is instead assumed to be present in
system-wide UAPI header. This breaks isolated environments that don't
have kernel UAPI headers installed system-wide, like BPF CI ([0]).

To fix this, bring in include/uapi/linux/stddef.h into tools/include.
We can't just copy/paste it, though, it has to be processed with
scripts/headers_install.sh, which has a dependency on scripts/unifdef.
So the full command to (re-)generate stddef.h for inclusion into
tools/include directory is:

  $ make scripts_unifdef && \
    cp $KBUILD_OUTPUT/scripts/unifdef scripts/ && \
    scripts/headers_install.sh include/uapi/linux/stddef.h tools/include/uapi/linux/stddef.h

This assumes KBUILD_OUTPUT envvar is set and used for out-of-tree builds.

  [0] https://github.com/kernel-patches/bpf/actions/runs/3379432493/jobs/5610982609



Fixes: 036b8f5b ("tools headers uapi: Update linux/in.h copy")
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/bpf/20221102182517.2675301-2-andrii@kernel.org
parent aec1dc97

tools/include/uapi/linux/in.h

+1 −0
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ 
#define _UAPI_LINUX_IN_H



#include <linux/types.h>

#include <linux/stddef.h>

#include <linux/libc-compat.h>

#include <linux/socket.h>

tools/include/uapi/linux/stddef.h

0 → 100644
+47 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */

#ifndef _LINUX_STDDEF_H

#define _LINUX_STDDEF_H







#ifndef __always_inline

#define __always_inline __inline__

#endif



/**

 * __struct_group() - Create a mirrored named and anonyomous struct

 *

 * @TAG: The tag name for the named sub-struct (usually empty)

 * @NAME: The identifier name of the mirrored sub-struct

 * @ATTRS: Any struct attributes (usually empty)

 * @MEMBERS: The member declarations for the mirrored structs

 *

 * Used to create an anonymous union of two structs with identical layout

 * and size: one anonymous and one named. The former's members can be used

 * normally without sub-struct naming, and the latter can be used to

 * reason about the start, end, and size of the group of struct members.

 * The named struct can also be explicitly tagged for layer reuse, as well

 * as both having struct attributes appended.

 */

#define __struct_group(TAG, NAME, ATTRS, MEMBERS...) \

	union { \

		struct { MEMBERS } ATTRS; \

		struct TAG { MEMBERS } ATTRS NAME; \

	}



/**

 * __DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union

 *

 * @TYPE: The type of each flexible array element

 * @NAME: The name of the flexible array member

 *

 * In order to have a flexible array member in a union or alone in a

 * struct, it needs to be wrapped in an anonymous struct with at least 1

 * named member, but that member can be empty.

 */

#define __DECLARE_FLEX_ARRAY(TYPE, NAME)	\

	struct { \

		struct { } __empty_ ## NAME; \

		TYPE NAME[]; \

	}

#endif