Re: "arm64: vdso: Substitute gettimeofday() with C implementation" breaks clang build

[Vincenzo Frascino]

Hi Qian,

On 25/06/2019 13:16, Qian Cai wrote:
> The linux-next commit "arm64: vdso: Substitute gettimeofday() with C
> implementation" [1] breaks clang build.
> 
> error: invalid value 'tiny' in '-mcode-model tiny'
> make[1]: *** [scripts/Makefile.build:279:
> arch/arm64/kernel/vdso/vgettimeofday.o] Error 1
> make[1]: *** Waiting for unfinished jobs....
> make: *** [arch/arm64/Makefile:180: vdso_prepare] Error 2
> 
> [1] https://patchwork.kernel.org/patch/11009663/
> 

I am not sure what does exactly break from your report. Could you please provide
more details?

On my env:

$ make mrproper && make defconfig && make CC=clang HOSTCC=clang -j$(nproc)

...

arch/arm64/Makefile:56: CROSS_COMPILE_COMPAT is clang, the compat vDSO will not
be built

...

  LDS     arch/arm64/kernel/vdso/vdso.lds
  AS      arch/arm64/kernel/vdso/note.o
  AS      arch/arm64/kernel/vdso/sigreturn.o
  CC      arch/arm64/kernel/vdso/vgettimeofday.o
  LD      arch/arm64/kernel/vdso/vdso.so.dbg
  VDSOCHK arch/arm64/kernel/vdso/vdso.so.dbg
  VDSOSYM include/generated/vdso-offsets.h

...

  LD      vmlinux.o
  MODPOST vmlinux.o
  MODINFO modules.builtin.modinfo
  KSYM    .tmp_kallsyms1.o
  KSYM    .tmp_kallsyms2.o
  LD      vmlinux
  SORTEX  vmlinux
  SYSMAP  System.map
  Building modules, stage 2.
  OBJCOPY arch/arm64/boot/Image
  MODPOST 483 modules

-- 
Regards,
Vincenzo