Re: [PATCH v4 2/2] kbuild: Cache a few more calls to the compiler

From: Doug Anderson
Date: Wed Dec 20 2017 - 12:11:59 EST


Hi,

On Tue, Dec 19, 2017 at 5:18 PM, Dave Hansen <dave.hansen@xxxxxxxxx> wrote:
> I'm seeing some build breakage that I bisected to commit 4e56207130eda:
>
>> CC kernel/bounds.s
>> In file included from /home/davehans/linux.git/include/asm-generic/bug.h:15:0,
>> from /home/davehans/linux.git/arch/x86/include/asm/bug.h:81,
>> from /home/davehans/linux.git/include/linux/bug.h:4,
>> from /home/davehans/linux.git/include/linux/page-flags.h:9,
>> from /home/davehans/linux.git/kernel/bounds.c:9:
>> /home/davehans/linux.git/include/linux/kernel.h:5:20: fatal error: stdarg.h: No such file or directory
>> #include <stdarg.h>
>> ^
>> compilation terminated.
>
> It's odd because I'm pretty sure I've done 4.15-rc compiles on this
> system before without issues. I suspect something in my config
> (attached) is triggering this.
>
> Does this look familiar to anyone?
>
> gcc -v
> Using built-in specs.
> COLLECT_GCC=/usr/bin/gcc
> COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-redhat-linux/6.4.1/lto-wrapper
> Target: x86_64-redhat-linux
> Configured with: ../configure --enable-bootstrap
> --enable-languages=c,c++,objc,obj-c++,fortran,ada,go,lto --prefix=/usr
> --mandir=/usr/share/man --infodir=/usr/share/info
> --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-shared
> --enable-threads=posix --enable-checking=release --enable-multilib
> --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions
> --enable-gnu-unique-object --enable-linker-build-id
> --with-linker-hash-style=gnu --enable-plugin --enable-initfini-array
> --disable-libgcj --with-isl --enable-libmpx
> --enable-gnu-indirect-function --with-tune=generic --with-arch_32=i686
> --build=x86_64-redhat-linux
> Thread model: posix
> gcc version 6.4.1 20170727 (Red Hat 6.4.1-1) (GCC)

Yes, it appears to be related to upgrading your compiler without doing
a "make clean". Discussion can be found at
<https://lkml.org/lkml/2017/12/16/315>, or search for the subject

[BUG] Build error for 4.15-rc3 kernel caused by patch "kbuild: Add a
cache for generated variables"

-Doug