Commit 50560ce6 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'kbuild-gnu11-v5.18' of... 

Merge tag 'kbuild-gnu11-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild update for C11 language base from Masahiro Yamada:
 "Kbuild -std=gnu11 updates for v5.18

  Linus pointed out the benefits of C99 some years ago, especially
  variable declarations in loops [1]. At that time, we were not ready
  for the migration due to old compilers.

  Recently, Jakob Koschel reported a bug in list_for_each_entry(), which
  leaks the invalid pointer out of the loop [2]. In the discussion, we
  agreed that the time had come. Now that GCC 5.1 is the minimum
  compiler version, there is nothing to prevent us from going to
  -std=gnu99, or even straight to -std=gnu11.

  Discussions for a better list iterator implementation are ongoing, but
  this patch set must land first"

[1] https://lore.kernel.org/all/CAHk-=wgr12JkKmRd21qh-se-_Gs69kbPgR9x4C+Es-yJV2GLkA@mail.gmail.com/
[2] https://lore.kernel.org/lkml/86C4CE7D-6D93-456B-AA82-F8ADEACA40B7@gmail.com/

* tag 'kbuild-gnu11-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  Kbuild: use -std=gnu11 for KBUILD_USERCFLAGS
  Kbuild: move to -std=gnu11
  Kbuild: use -Wdeclaration-after-statement
  Kbuild: add -Wno-shift-negative-value where -Wextra is used
parents 29c8c183 1e240781

Documentation/process/programming-language.rst

+3 −3
Original line number Diff line number Diff line
@@ -5,9 +5,9 @@ Programming Language 


The kernel is written in the C programming language [c-language]_.

More precisely, the kernel is typically compiled with ``gcc`` [gcc]_

under ``-std=gnu89`` [gcc-c-dialect-options]_: the GNU dialect of ISO C90

(including some C99 features). ``clang`` [clang]_ is also supported, see

docs on :ref:`Building Linux with Clang/LLVM <kbuild_llvm>`.

under ``-std=gnu11`` [gcc-c-dialect-options]_: the GNU dialect of ISO C11.

``clang`` [clang]_ is also supported, see docs on

:ref:`Building Linux with Clang/LLVM <kbuild_llvm>`.



This dialect contains many extensions to the language [gnu-extensions]_,

and many of them are used within the kernel as a matter of course.

Documentation/translations/it_IT/process/programming-language.rst

+2 −2
Original line number Diff line number Diff line
@@ -10,8 +10,8 @@ Linguaggio di programmazione 


Il kernel è scritto nel linguaggio di programmazione C [it-c-language]_.

Più precisamente, il kernel viene compilato con ``gcc`` [it-gcc]_ usando

l'opzione ``-std=gnu89`` [it-gcc-c-dialect-options]_: il dialetto GNU

dello standard ISO C90 (con l'aggiunta di alcune funzionalità da C99).

l'opzione ``-std=gnu11`` [it-gcc-c-dialect-options]_: il dialetto GNU

dello standard ISO C11.

Linux supporta anche ``clang`` [it-clang]_, leggete la documentazione

:ref:`Building Linux with Clang/LLVM <kbuild_llvm>`.

Documentation/translations/zh_CN/process/programming-language.rst

+1 −2
Original line number Diff line number Diff line
@@ -9,8 +9,7 @@ 
============



内核是用C语言 :ref:`c-language <cn_c-language>` 编写的。更准确地说，内核通常是用 :ref:`gcc <cn_gcc>`

在 ``-std=gnu89`` :ref:`gcc-c-dialect-options <cn_gcc-c-dialect-options>` 下编译的：ISO C90的 GNU 方言（

包括一些C99特性）

在 ``-std=gnu11`` :ref:`gcc-c-dialect-options <cn_gcc-c-dialect-options>` 下编译的：ISO C11的 GNU 方言



这种方言包含对语言 :ref:`gnu-extensions <cn_gnu-extensions>` 的许多扩展，当然，它们许多都在内核中使用。

Documentation/translations/zh_TW/process/programming-language.rst

+1 −2
Original line number Diff line number Diff line
@@ -12,8 +12,7 @@ 
============



內核是用C語言 :ref:`c-language <tw_c-language>` 編寫的。更準確地說，內核通常是用 :ref:`gcc <tw_gcc>`

在 ``-std=gnu89`` :ref:`gcc-c-dialect-options <tw_gcc-c-dialect-options>` 下編譯的：ISO C90的 GNU 方言（

包括一些C99特性）

在 ``-std=gnu11`` :ref:`gcc-c-dialect-options <tw_gcc-c-dialect-options>` 下編譯的：ISO C11的 GNU 方言



這種方言包含對語言 :ref:`gnu-extensions <tw_gnu-extensions>` 的許多擴展，當然，它們許多都在內核中使用。

Makefile

+4 −3
Original line number Diff line number Diff line
@@ -432,7 +432,8 @@ HOSTCXX = g++ 
endif



export KBUILD_USERCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \

			      -O2 -fomit-frame-pointer -std=gnu89

			      -O2 -fomit-frame-pointer -std=gnu11 \

			      -Wdeclaration-after-statement

export KBUILD_USERLDFLAGS :=



KBUILD_HOSTCFLAGS   := $(KBUILD_USERCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
@@ -515,7 +516,7 @@ KBUILD_CFLAGS := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \ 
		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \

		   -Werror=implicit-function-declaration -Werror=implicit-int \

		   -Werror=return-type -Wno-format-security \

		   -std=gnu89

		   -std=gnu11

KBUILD_CPPFLAGS := -D__KERNEL__

KBUILD_AFLAGS_KERNEL :=

KBUILD_CFLAGS_KERNEL :=
@@ -782,7 +783,7 @@ KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH) 


ifdef CONFIG_CC_IS_CLANG

KBUILD_CPPFLAGS += -Qunused-arguments

# The kernel builds with '-std=gnu89' so use of GNU extensions is acceptable.

# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.

KBUILD_CFLAGS += -Wno-gnu

# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the

# source of a reference will be _MergedGlobals and not on of the whitelisted names.