Changes in stddef.h

5d0d3623303775d750e122a2542d1a26c8573d38 - Merge tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux

Tue, 14 Apr 2026 16:18:40 +0000

Merge tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linuxPull Kbuild/Kconfig updates from Nicolas Schier: "Kbuild: - reject unexpected values for LLVM= - uapi: remove usage of toolchain headers - switch from '-fms-extensions' to '-fms-anonymous-structs' when available (currently: clang >= 23.0.0) - reduce the number of compiler-generated suffixes for clang thin-lto build - reduce output spam ("GEN Makefile") when building out of tree - improve portability for testing headers - also test UAPI headers against C++ compilers - drop build ID architecture allow-list in vdso_install - only run checksyscalls when necessary - update the debug information notes in reproducible-builds.rst - expand inlining hints with -fdiagnostics-show-inlining-chain Kconfig: - forbid multiple entries with the same symbol in a choice - error out on duplicated kconfig inclusion"* tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (35 commits) kbuild: expand inlining hints with -fdiagnostics-show-inlining-chain kconfig: forbid multiple entries with the same symbol in a choice Documentation: kbuild: Update the debug information notes in reproducible-builds.rst checksyscalls: move instance functionality into generic code checksyscalls: only run when necessary checksyscalls: fail on all intermediate errors checksyscalls: move path to reference table to a variable kbuild: vdso_install: drop build ID architecture allow-list kbuild: vdso_install: gracefully handle images without build ID kbuild: vdso_install: hide readelf warnings kbuild: vdso_install: split out the readelf invocation kbuild: uapi: also test UAPI headers against C++ compilers kbuild: uapi: provide a C++ compatible dummy definition of NULL kbuild: uapi: handle UML in architecture-specific exclusion lists kbuild: uapi: move all include path flags together kbuild: uapi: move some compiler arguments out of the command definition check-uapi: use dummy libc includes check-uapi: honor ${CROSS_COMPILE} setting check-uapi: link into shared objects kbuild: reduce output spam when building out of tree ... List of files: /linux/usr/dummy-include/stddef.h

b187c1a1a0513593663b1adee0340d41d833d16d - kbuild: uapi: provide a C++ compatible dummy definition of NULL

Mon, 16 Mar 2026 16:52:01 +0000

kbuild: uapi: provide a C++ compatible dummy definition of NULLNULL works differently in C++ compared to C.To allow testing the UAPI headers against C++ compilers, providea variant of NULL which works with those.Signed-off-by: Thomas Weißschuh Reviewed-by: Nathan Chancellor Link: https://patch.msgid.link/20260316-kbuild-uapi-c-v2-4-35d6d0ed863f@weissschuh.netSigned-off-by: Nicolas Schier List of files: /linux/usr/dummy-include/stddef.h

aad94ba683adc6ff7ff4e29ae48184b42782dd97 - kbuild: uapi: provide stub includes for some libc headers

Fri, 27 Feb 2026 06:38:04 +0000

kbuild: uapi: provide stub includes for some libc headersSome UAPI headers incorrectly use libc headers. To compile-test theseUAPI headers, their respective libc dependencies need to be present.Not all kernel toolchains provide these headers, reducing test coverage.Introduce some stub headers which provide just enough symbols to testall UAPI headers. Most headers are empty anyways, as their symbols areonly used in macros which are not actually evaluated.As these headers are only ever used with newer kernel toolchains, theycan defer to compiler builtins in many cases.As more UAPI headers are cleaned up to not require these stubs anymore,they can be removed again.Signed-off-by: Thomas Weißschuh Reviewed-by: Nathan Chancellor Reviewed-by: Nicolas Schier Tested-by: Nicolas Schier Acked-by: Arnd Bergmann Link: https://patch.msgid.link/20260227-kbuild-uapi-libc-v1-6-c17de0d19776@weissschuh.netSigned-off-by: Nicolas Schier List of files: /linux/usr/dummy-include/stddef.h