[tip:x86/build 2/2] kernel/bounds.c:1: error: -mpreferred-stack-boundary=3 is not between 4 and 12

[tip:x86/build 2/2] kernel/bounds.c:1: error: -mpreferred-stack-boundary=3 is not between 4 and 12

[kbuild test robot]

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tree:   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/build
head:   8f91869766c00622b2eaa8ee567db4f333b78c1a
commit: 8f91869766c00622b2eaa8ee567db4f333b78c1a [2/2] x86/build: Fix stack alignment for CLang
config: x86_64-randconfig-b0-08172108 (attached as .config)
compiler: gcc-4.4 (Debian 4.4.7-8) 4.4.7
reproduce:
        git checkout 8f91869766c00622b2eaa8ee567db4f333b78c1a
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

>> kernel/bounds.c:1: error: -mpreferred-stack-boundary=3 is not between 4 and 12
   make[2]: *** [kernel/bounds.s] Error 1
   make[2]: Target '__build' not remade because of errors.
   make[1]: *** [prepare0] Error 2
   make[1]: Target 'prepare' not remade because of errors.
   make: *** [sub-make] Error 2

vim +1 kernel/bounds.c

1cdf25d7 Christoph Lameter 2008-04-28 @1  /*
1cdf25d7 Christoph Lameter 2008-04-28  2   * Generate definitions needed by the preprocessor.
1cdf25d7 Christoph Lameter 2008-04-28  3   * This code generates raw asm output which is post-processed
1cdf25d7 Christoph Lameter 2008-04-28  4   * to extract and format the required data.
1cdf25d7 Christoph Lameter 2008-04-28  5   */
1cdf25d7 Christoph Lameter 2008-04-28  6  

:::::: The code at line 1 was first introduced by commit
:::::: 1cdf25d704f7951d02a04064c97db547d6021872 kbuild: create a way to create preprocessor constants from C expressions

:::::: TO: Christoph Lameter <clameter@sgi.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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Re: [tip:x86/build 2/2] kernel/bounds.c:1: error: -mpreferred-stack-boundary=3 is not between 4 and 12

[Matthias Kaehlcke]

El Thu, Aug 17, 2017 at 10:13:20PM +0800 kbuild test robot ha dit:

> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/build
> head:   8f91869766c00622b2eaa8ee567db4f333b78c1a
> commit: 8f91869766c00622b2eaa8ee567db4f333b78c1a [2/2] x86/build: Fix stack alignment for CLang
> config: x86_64-randconfig-b0-08172108 (attached as .config)
> compiler: gcc-4.4 (Debian 4.4.7-8) 4.4.7
> reproduce:
>         git checkout 8f91869766c00622b2eaa8ee567db4f333b78c1a
>         # save the attached .config to linux build tree
>         make ARCH=x86_64 
> 
> All errors (new ones prefixed by >>):
> 
> >> kernel/bounds.c:1: error: -mpreferred-stack-boundary=3 is not between 4 and 12

To be honest I was slightly concerned about not checking the actual
option that is applied, but expected it to be ok.

Though we can't use cc-option directly to chose between the gcc and
the clang option in this case we can use it to make sure only valid
parameters are applied. I'll prepare a fix for the fix.

Matthias