powerpc: nvram_64.c:75:13: error: 'oops_to_nvram' used but never defined [-Werror]

powerpc: nvram_64.c:75:13: error: 'oops_to_nvram' used but never defined [-Werror]

[Naresh Kamboju]

The powerpc builds failed on Linux next-20240626 tag due to following warnings
and errors with gcc-13, gcc-8 and clang-18.

Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>

Regressions found on powerpc:

  - clang-nightly-ppc64e_defconfig
  - clang-18-maple_defconfig
  - clang-nightly-defconfig
  - clang-18-defconfig
  - gcc-13-maple_defconfig
  - gcc-8-cell_defconfig
  - gcc-8-maple_defconfig
  - clang-18-ppc64e_defconfig
  - clang-nightly-cell_defconfig
  - clang-nightly-maple_defconfig
  - gcc-8-ppc64e_defconfig
  - gcc-13-cell_defconfig
  - gcc-13-defconfig
  - gcc-13-ppc64e_defconfig
  - clang-18-cell_defconfig
  - gcc-8-defconfig

Build errors:
----
arch/powerpc/kernel/nvram_64.c:79:17: error: initialization of 'void
(*)(struct kmsg_dumper *, enum kmsg_dump_reason,  const char *)' from
incompatible pointer type 'void (*)(struct kmsg_dumper *, enum
kmsg_dump_reason)' [-Werror=incompatible-pointer-types]
   79 |         .dump = oops_to_nvram
      |                 ^~~~~~~~~~~~~
arch/powerpc/kernel/nvram_64.c:79:17: note: (near initialization for
'nvram_kmsg_dumper.dump')
arch/powerpc/kernel/nvram_64.c:645:13: error: conflicting types for
'oops_to_nvram'; have 'void(struct kmsg_dumper *, enum
kmsg_dump_reason,  const char *)'
  645 | static void oops_to_nvram(struct kmsg_dumper *dumper,
      |             ^~~~~~~~~~~~~
arch/powerpc/kernel/nvram_64.c:75:13: note: previous declaration of
'oops_to_nvram' with type 'void(struct kmsg_dumper *, enum
kmsg_dump_reason)'
   75 | static void oops_to_nvram(struct kmsg_dumper *dumper,
      |             ^~~~~~~~~~~~~
arch/powerpc/kernel/nvram_64.c:75:13: error: 'oops_to_nvram' used but
never defined [-Werror]
arch/powerpc/kernel/nvram_64.c:645:13: error: 'oops_to_nvram' defined
but not used [-Werror=unused-function]
  645 | static void oops_to_nvram(struct kmsg_dumper *dumper,
      |             ^~~~~~~~~~~~~
cc1: all warnings being treated as errors

metadata:
--
  git_describe: next-20240626
  git_repo: https://gitlab.com/Linaro/lkft/mirrors/next/linux-next
  git_short_log: df9574a57d02 ("Add linux-next specific files for 20240626")
  arch: powerpc
  toolchain: gcc-13, gcc-8 and clang-18

Steps to reproduce:
---------

# tuxmake --runtime podman --target-arch powerpc --toolchain gcc-13
--kconfig ppc64e_defconfig


Links:
--
 - https://storage.tuxsuite.com/public/linaro/lkft/builds/2iQqkMfvFPihkYnvWC7UxrVhb1X/
 - https://qa-reports.linaro.org/lkft/linux-next-master/build/next-20240626/testrun/24453163/suite/build/test/gcc-13-ppc64e_defconfig/details/
- https://storage.tuxsuite.com/public/linaro/lkft/builds/2iQqkMfvFPihkYnvWC7UxrVhb1X/config

--
Linaro LKFT
https://lkft.linaro.org

Re: powerpc: nvram_64.c:75:13: error: 'oops_to_nvram' used but never defined [-Werror]

[Arnd Bergmann]

On Thu, Jun 27, 2024, at 14:49, Naresh Kamboju wrote:
> The powerpc builds failed on Linux next-20240626 tag due to following 
> ----
> arch/powerpc/kernel/nvram_64.c:79:17: error: initialization of 'void
> (*)(struct kmsg_dumper *, enum kmsg_dump_reason,  const char *)' from
> incompatible pointer type 'void (*)(struct kmsg_dumper *, enum
> kmsg_dump_reason)' [-Werror=incompatible-pointer-types]
>    79 |         .dump = oops_to_nvram
>       |                 ^~~~~~~~~~~~~
> arch/powerpc/kernel/nvram_64.c:79:17: note: (near initialization for
> 'nvram_kmsg_dumper.dump')
> arch/powerpc/kernel/nvram_64.c:645:13: error: conflicting types for
> 'oops_to_nvram'; have 'void(struct kmsg_dumper *, enum
> kmsg_dump_reason,  const char *)'
>   645 | static void oops_to_nvram(struct kmsg_dumper *dumper,
>       |             ^~~~~~~~~~~~~
> arch/powerpc/kernel/nvram_64.c:75:13: note: previous declaration of
> 'oops_to_nvram' with type 'void(struct kmsg_dumper *, enum
> kmsg_dump_reason)'
>    75 | static void oops_to_nvram(struct kmsg_dumper *dumper,
>       |             ^~~~~~~~~~~~~
> arch/powerpc/kernel/nvram_64.c:75:13: error: 'oops_to_nvram' used but
> never defined [-Werror]
> arch/powerpc/kernel/nvram_64.c:645:13: error: 'oops_to_nvram' defined
> but not used [-Werror=unused-function]
>   645 | static void oops_to_nvram(struct kmsg_dumper *dumper,
>       |             ^~~~~~~~~~~~~
> cc1: all warnings being treated as error

The problem is the forward declaration that was not changed
as part of commit 7e72bb7504d1 ("printk: add a short
description string to kmsg_dump()"). This should fix it:

diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
index e385d3164648..a9da83c4243a 100644
--- a/arch/powerpc/kernel/nvram_64.c
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -73,7 +73,8 @@ static const char *nvram_os_partitions[] = {
 };
 
 static void oops_to_nvram(struct kmsg_dumper *dumper,
-			  enum kmsg_dump_reason reason);
+			  enum kmsg_dump_reason reason,
+			  const char *desc);
 
 static struct kmsg_dumper nvram_kmsg_dumper = {
 	.dump = oops_to_nvram


      Arnd