Hi Pawel,
FYI, the error/warning still remains.
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
commit: 22447a99c97e353bde8f90c2353873f27681d57c drivers/soc/litex: add LiteX SoC Controller driver
date: 8 weeks ago
config: x86_64-randconfig-a001-20210107 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 5c951623bc8965fa1e89660f2f5f4a2944e4981a)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=22447a99c97e353bde8f90c2353873f27681d57c
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 22447a99c97e353bde8f90c2353873f27681d57c
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>):
>> drivers/soc/litex/litex_soc_ctrl.c:143:34: warning: unused variable 'litex_soc_ctrl_of_match' [-Wunused-const-variable]
static const struct of_device_id litex_soc_ctrl_of_match[] = {
^
1 warning generated.
vim +/litex_soc_ctrl_of_match +143 drivers/soc/litex/litex_soc_ctrl.c
142
> 143 static const struct of_device_id litex_soc_ctrl_of_match[] = {
144 {.compatible = "litex,soc-controller"},
145 {},
146 };
147
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
On Mon, Jan 11, 2021 at 09:30:55PM +0900, Stafford Horne wrote:
> On Thu, Jan 07, 2021 at 04:04:47AM +0800, kernel test robot wrote:
> > Hi Pawel,
> >
> > FYI, the error/warning still remains.
> >
> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > head: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
> > commit: 22447a99c97e353bde8f90c2353873f27681d57c drivers/soc/litex: add LiteX SoC Controller driver
> > date: 8 weeks ago
> > config: x86_64-randconfig-a001-20210107 (attached as .config)
> > compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 5c951623bc8965fa1e89660f2f5f4a2944e4981a)
> > reproduce (this is a W=1 build):
> > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> > chmod +x ~/bin/make.cross
> > # install x86_64 cross compiling tool for clang build
> > # apt-get install binutils-x86-64-linux-gnu
> > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=22447a99c97e353bde8f90c2353873f27681d57c
> > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> > git fetch --no-tags linus master
> > git checkout 22447a99c97e353bde8f90c2353873f27681d57c
> > # save the attached .config to linux build tree
> > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <[email protected]>
> >
> > All warnings (new ones prefixed by >>):
> >
> > >> drivers/soc/litex/litex_soc_ctrl.c:143:34: warning: unused variable 'litex_soc_ctrl_of_match' [-Wunused-const-variable]
> > static const struct of_device_id litex_soc_ctrl_of_match[] = {
> > ^
> > 1 warning generated.
> >
> >
> > vim +/litex_soc_ctrl_of_match +143 drivers/soc/litex/litex_soc_ctrl.c
> >
> > 142
> > > 143 static const struct of_device_id litex_soc_ctrl_of_match[] = {
> > 144 {.compatible = "litex,soc-controller"},
> > 145 {},
> > 146 };
> > 147
> >
>
> I don't use clang but GCC, and I cannot reproduce this warning.
>
> $ make drivers/soc/litex/litex_soc_ctrl.o
> CALL scripts/checksyscalls.sh
> CALL scripts/atomic/check-atomics.sh
> DESCEND objtool
> CC drivers/soc/litex/litex_soc_ctrl.o
>
> Also, I can see litex_soc_ctrl_of_match is used. I am not sure what is going on
> here.
>
> -Stafford
>
You need W=1
$ make -skj"$(nproc)" W=1 olddefconfig drivers/soc/litex/litex_soc_ctrl.o
drivers/soc/litex/litex_soc_ctrl.c:143:34: warning: ‘litex_soc_ctrl_of_match’ defined but not used [-Wunused-const-variable=]
143 | static const struct of_device_id litex_soc_ctrl_of_match[] = {
| ^~~~~~~~~~~~~~~~~~~~~~~
$ rg "CONFIG_OF|CONFIG_LITEX_SOC_CONTROLLER" .config
1124:# CONFIG_OF is not set
4673:CONFIG_LITEX_SOC_CONTROLLER=y
This variable is used in two places in that file, in the
MODULE_DEVICE_TABLE macro and the of_match_ptr macro. When CONFIG_OF is
disabled, of_match_ptr evaluates to NULL. When the file is built into
the kernel image, MODULE_DEVICE_TABLE evaluates to nothing, leaving this
variable defined but unused in the final preprocessed source.
Hope that helps!
Cheers,
Nathan
On Thu, Jan 07, 2021 at 04:04:47AM +0800, kernel test robot wrote:
> Hi Pawel,
>
> FYI, the error/warning still remains.
>
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
> commit: 22447a99c97e353bde8f90c2353873f27681d57c drivers/soc/litex: add LiteX SoC Controller driver
> date: 8 weeks ago
> config: x86_64-randconfig-a001-20210107 (attached as .config)
> compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 5c951623bc8965fa1e89660f2f5f4a2944e4981a)
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # install x86_64 cross compiling tool for clang build
> # apt-get install binutils-x86-64-linux-gnu
> # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=22447a99c97e353bde8f90c2353873f27681d57c
> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> git fetch --no-tags linus master
> git checkout 22447a99c97e353bde8f90c2353873f27681d57c
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <[email protected]>
>
> All warnings (new ones prefixed by >>):
>
> >> drivers/soc/litex/litex_soc_ctrl.c:143:34: warning: unused variable 'litex_soc_ctrl_of_match' [-Wunused-const-variable]
> static const struct of_device_id litex_soc_ctrl_of_match[] = {
> ^
> 1 warning generated.
>
>
> vim +/litex_soc_ctrl_of_match +143 drivers/soc/litex/litex_soc_ctrl.c
>
> 142
> > 143 static const struct of_device_id litex_soc_ctrl_of_match[] = {
> 144 {.compatible = "litex,soc-controller"},
> 145 {},
> 146 };
> 147
>
I don't use clang but GCC, and I cannot reproduce this warning.
$ make drivers/soc/litex/litex_soc_ctrl.o
CALL scripts/checksyscalls.sh
CALL scripts/atomic/check-atomics.sh
DESCEND objtool
CC drivers/soc/litex/litex_soc_ctrl.o
Also, I can see litex_soc_ctrl_of_match is used. I am not sure what is going on
here.
-Stafford
On Mon, Jan 11, 2021 at 09:43:34AM -0700, Nathan Chancellor wrote:
> On Mon, Jan 11, 2021 at 09:30:55PM +0900, Stafford Horne wrote:
> > On Thu, Jan 07, 2021 at 04:04:47AM +0800, kernel test robot wrote:
> > > Hi Pawel,
> > >
> > > FYI, the error/warning still remains.
> > >
> > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > > head: e71ba9452f0b5b2e8dc8aa5445198cd9214a6a62
> > > commit: 22447a99c97e353bde8f90c2353873f27681d57c drivers/soc/litex: add LiteX SoC Controller driver
> > > date: 8 weeks ago
> > > config: x86_64-randconfig-a001-20210107 (attached as .config)
> > > compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 5c951623bc8965fa1e89660f2f5f4a2944e4981a)
> > > reproduce (this is a W=1 build):
> > > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> > > chmod +x ~/bin/make.cross
> > > # install x86_64 cross compiling tool for clang build
> > > # apt-get install binutils-x86-64-linux-gnu
> > > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=22447a99c97e353bde8f90c2353873f27681d57c
> > > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> > > git fetch --no-tags linus master
> > > git checkout 22447a99c97e353bde8f90c2353873f27681d57c
> > > # save the attached .config to linux build tree
> > > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
> > >
> > > If you fix the issue, kindly add following tag as appropriate
> > > Reported-by: kernel test robot <[email protected]>
> > >
> > > All warnings (new ones prefixed by >>):
> > >
> > > >> drivers/soc/litex/litex_soc_ctrl.c:143:34: warning: unused variable 'litex_soc_ctrl_of_match' [-Wunused-const-variable]
> > > static const struct of_device_id litex_soc_ctrl_of_match[] = {
> > > ^
> > > 1 warning generated.
> > >
> > >
> > > vim +/litex_soc_ctrl_of_match +143 drivers/soc/litex/litex_soc_ctrl.c
> > >
> > > 142
> > > > 143 static const struct of_device_id litex_soc_ctrl_of_match[] = {
> > > 144 {.compatible = "litex,soc-controller"},
> > > 145 {},
> > > 146 };
> > > 147
> > >
> >
> > I don't use clang but GCC, and I cannot reproduce this warning.
> >
> > $ make drivers/soc/litex/litex_soc_ctrl.o
> > CALL scripts/checksyscalls.sh
> > CALL scripts/atomic/check-atomics.sh
> > DESCEND objtool
> > CC drivers/soc/litex/litex_soc_ctrl.o
> >
> > Also, I can see litex_soc_ctrl_of_match is used. I am not sure what is going on
> > here.
> >
> > -Stafford
> >
>
> You need W=1
>
> $ make -skj"$(nproc)" W=1 olddefconfig drivers/soc/litex/litex_soc_ctrl.o
> drivers/soc/litex/litex_soc_ctrl.c:143:34: warning: ‘litex_soc_ctrl_of_match’ defined but not used [-Wunused-const-variable=]
> 143 | static const struct of_device_id litex_soc_ctrl_of_match[] = {
> | ^~~~~~~~~~~~~~~~~~~~~~~
>
> $ rg "CONFIG_OF|CONFIG_LITEX_SOC_CONTROLLER" .config
> 1124:# CONFIG_OF is not set
> 4673:CONFIG_LITEX_SOC_CONTROLLER=y
>
> This variable is used in two places in that file, in the
> MODULE_DEVICE_TABLE macro and the of_match_ptr macro. When CONFIG_OF is
> disabled, of_match_ptr evaluates to NULL. When the file is built into
> the kernel image, MODULE_DEVICE_TABLE evaluates to nothing, leaving this
> variable defined but unused in the final preprocessed source.
>
> Hope that helps!
That helps, I noticed it was only used in those macros so that was fishy. I
forgot to add W=1.
We will need to surround the definition in:
#if defined(CONFIG_OF)
#endif /* CONFIG_OF */