linux.git/usr/include/Makefile, branch master Linux kernel source tree kbuild: uapi: drop dependency on CC_CAN_LINK 2026-01-16T22:02:11+00:00 Thomas Weißschuh thomas.weissschuh@linutronix.de 2025-12-23T07:04:12+00:00 2a0a30805a7d27470e02137cae72f7c3188e44eb The header tests try to compile each header. Some UAPI headers depend on libc headers so they need a full userspace toolchain to build. This dependency is expressed in kconfig as a dependency on CC_CAN_LINK. Many kernel builds do not satisfy CC_CAN_LINK as they only use a minimal kernel (cross-) compiler. In those configurations the UAPI headers are not tested at all. However most UAPI headers do not even depend on any libc headers, and such dependencies are undesired in any case. Also the static analysis performed by headers_check.pl does not need CC_CAN_LINK. Drop the hard dependency on CC_CAN_LINK and instead skip the affected compilation step for exactly those headers which require libc. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-5-d91545d794f7@linutronix.de Signed-off-by: Nathan Chancellor <nathan@kernel.org> 
The header tests try to compile each header. Some UAPI headers depend on
libc headers so they need a full userspace toolchain to build. This
dependency is expressed in kconfig as a dependency on CC_CAN_LINK.
Many kernel builds do not satisfy CC_CAN_LINK as they only use a
minimal kernel (cross-) compiler. In those configurations the UAPI
headers are not tested at all.

However most UAPI headers do not even depend on any libc headers,
and such dependencies are undesired in any case. Also the static
analysis performed by headers_check.pl does not need CC_CAN_LINK.

Drop the hard dependency on CC_CAN_LINK and instead skip the affected
compilation step for exactly those headers which require libc.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-5-d91545d794f7@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
kbuild: uapi: split out command conditions into variables 2026-01-06T22:07:32+00:00 Thomas Weißschuh thomas.weissschuh@linutronix.de 2025-12-23T07:04:11+00:00 4ac85d9bc73ed38a3bf98a58f9a44087375332b4 The condition logic will become a bit more complicated. Split them out into dedicated variables so they stay readable. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-4-d91545d794f7@linutronix.de Signed-off-by: Nathan Chancellor <nathan@kernel.org> 
The condition logic will become a bit more complicated.

Split them out into dedicated variables so they stay readable.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-4-d91545d794f7@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
kbuild: uapi: don't compile test bpf_perf_event.h on xtensa 2026-01-06T22:07:32+00:00 Thomas Weißschuh thomas.weissschuh@linutronix.de 2025-12-23T07:04:10+00:00 e2772ba5f43df6b13b04041fe52b07e8cac06ce0 The xtensa UAPI headers do not provide 'struct pt_regs', triggering an error: usr/include/linux/bpf_perf_event.h:14:28: error: field 'regs' has incomplete type Disable the header tests for this file on xtensa. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-3-d91545d794f7@linutronix.de Signed-off-by: Nathan Chancellor <nathan@kernel.org> 
The xtensa UAPI headers do not provide 'struct pt_regs',
triggering an error:

usr/include/linux/bpf_perf_event.h:14:28: error: field 'regs' has incomplete type

Disable the header tests for this file on xtensa.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-3-d91545d794f7@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
kbuild: uapi: validate that headers do not use libc 2026-01-06T22:07:32+00:00 Thomas Weißschuh thomas.weissschuh@linutronix.de 2025-12-23T07:04:08+00:00 6059b880a93c38a90d178b49fa80403c76d1a89f The UAPI headers should be self-contained. That means they should not use other headers from libc. Currently this is not enforced and various dependencies have crept in. Add a check to make sure no new ones are added. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-1-d91545d794f7@linutronix.de Signed-off-by: Nathan Chancellor <nathan@kernel.org> 
The UAPI headers should be self-contained. That means they should not
use other headers from libc. Currently this is not enforced and various
dependencies have crept in.

Add a check to make sure no new ones are added.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20251223-uapi-nostdinc-v1-1-d91545d794f7@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
kbuild: uapi: reuse KBUILD_USERCFLAGS 2025-11-08T11:17:59+00:00 Thomas Weißschuh thomas.weissschuh@linutronix.de 2025-10-14T05:55:32+00:00 c4cb34aee13785d032b30e750214d2e1a486a242 The toplevel Makefile already provides the compiler flags necessary to build userspace applications for the target. Make use of them instead of duplicating the logic. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://patch.msgid.link/20251014-kbuild-uapi-usercflags-v1-1-c162f9059c47@linutronix.de Signed-off-by: Nicolas Schier <nsc@kernel.org> 
The toplevel Makefile already provides the compiler flags necessary to
build userspace applications for the target.

Make use of them instead of duplicating the logic.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20251014-kbuild-uapi-usercflags-v1-1-c162f9059c47@linutronix.de
Signed-off-by: Nicolas Schier <nsc@kernel.org>
kbuild: uapi: fail header test on compiler warnings 2025-08-13T21:00:34+00:00 Thomas Weißschuh thomas.weissschuh@linutronix.de 2025-08-13T06:16:57+00:00 3788d69db18d310afa9892642520fb9b47edf829 Compiler warnings also indicate issues with the headers. Make sure they don't go unnoticed. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Nicolas Schier <nsc@kernel.org> Link: https://lore.kernel.org/r/20250813-kbuild-hdrtest-fixes-v2-2-8a7921ca3a03@linutronix.de Signed-off-by: Nathan Chancellor <nathan@kernel.org> 
Compiler warnings also indicate issues with the headers.

Make sure they don't go unnoticed.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://lore.kernel.org/r/20250813-kbuild-hdrtest-fixes-v2-2-8a7921ca3a03@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
kbuild: uapi: rerun header tests when headers_check.pl changes 2025-08-13T21:00:33+00:00 Thomas Weißschuh thomas.weissschuh@linutronix.de 2025-08-13T06:16:56+00:00 d4b7080be277ca400b443ac211b79450f4befddc If the checks change they need to be rerun. Add a Makefile dependency so this happens. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Nicolas Schier <nsc@kernel.org> Link: https://lore.kernel.org/r/20250813-kbuild-hdrtest-fixes-v2-1-8a7921ca3a03@linutronix.de Signed-off-by: Nathan Chancellor <nathan@kernel.org> 
If the checks change they need to be rerun.

Add a Makefile dependency so this happens.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://lore.kernel.org/r/20250813-kbuild-hdrtest-fixes-v2-1-8a7921ca3a03@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
usr/include: openrisc: don't HDRTEST bpf_perf_event.h 2025-05-12T06:03:17+00:00 Randy Dunlap rdunlap@infradead.org 2025-04-26T03:08:15+00:00 56045757accf5a51c9146585acd5f76fa4fbdb97 Since openrisc does not support PERF_EVENTS, omit the HDRTEST of bpf_perf_event.h for arch/openrisc/. Fixes a build error: usr/include/linux/bpf_perf_event.h:14:28: error: field 'regs' has incomplete type Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Stafford Horne <shorne@gmail.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 
Since openrisc does not support PERF_EVENTS, omit the HDRTEST of
bpf_perf_event.h for arch/openrisc/.

Fixes a build error:
usr/include/linux/bpf_perf_event.h:14:28: error: field 'regs' has incomplete type

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
kbuild: hdrcheck: fix cross build with clang 2025-03-04T19:06:45+00:00 Arnd Bergmann arnd@arndb.de 2025-02-25T10:00:31+00:00 02e9a22ceef0227175e391902d8760425fa072c6 The headercheck tries to call clang with a mix of compiler arguments that don't include the target architecture. When building e.g. x86 headers on arm64, this produces a warning like clang: warning: unknown platform, assuming -mfloat-abi=soft Add in the KBUILD_CPPFLAGS, which contain the target, in order to make it build properly. See also 1b71c2fb04e7 ("kbuild: userprogs: fix bitsize and target detection on clang"). Reviewed-by: Nathan Chancellor <nathan@kernel.org> Fixes: feb843a469fb ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS") Signed-off-by: Arnd Bergmann <arnd@arndb.de> 
The headercheck tries to call clang with a mix of compiler arguments
that don't include the target architecture. When building e.g. x86
headers on arm64, this produces a warning like

   clang: warning: unknown platform, assuming -mfloat-abi=soft

Add in the KBUILD_CPPFLAGS, which contain the target, in order to make it
build properly.

See also 1b71c2fb04e7 ("kbuild: userprogs: fix bitsize and target
detection on clang").

Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Fixes: feb843a469fb ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
kbuild: Drop support for include/asm-<arch> in headers_check.pl 2024-12-21T02:43:17+00:00 Geert Uytterhoeven geert+renesas@glider.be 2024-12-05T13:20:43+00:00 d67393f4d28ef0544eaf382f1123dcaf56495dc9 "include/asm-<arch>" was replaced by "arch/<arch>/include/asm" a long time ago. All assembler header files are now included using "#include <asm/*>", so there is no longer a need to rewrite paths. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 
"include/asm-<arch>" was replaced by "arch/<arch>/include/asm" a long
time ago.  All assembler header files are now included using
"#include <asm/*>", so there is no longer a need to rewrite paths.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>