* arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used
@ 2023-05-22 19:00 kernel test robot
2023-06-14 14:11 ` Christophe Leroy
0 siblings, 1 reply; 5+ messages in thread
From: kernel test robot @ 2023-05-22 19:00 UTC (permalink / raw)
To: Christophe Leroy
Cc: llvm, oe-kbuild-all, linux-kernel, Michael Ellerman,
Nathan Chancellor
Hi Christophe,
FYI, the error/warning still remains.
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 44c026a73be8038f03dbdeef028b642880cf1511
commit: 7245fc5bb7a966852d5bd7779d1f5855530b461a powerpc/math-emu: Remove -w build flag and fix warnings
date: 9 months ago
config: powerpc-randconfig-r022-20230522 (https://download.01.org/0day-ci/archive/20230523/202305230231.3Wb7Q68G-lkp@intel.com/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project b0fb98227c90adf2536c9ad644a74d5e92961111)
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 powerpc cross compiling tool for clang build
# apt-get install binutils-powerpc-linux-gnu
# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7245fc5bb7a966852d5bd7779d1f5855530b461a
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 7245fc5bb7a966852d5bd7779d1f5855530b461a
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/math-emu/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202305230231.3Wb7Q68G-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used [-Wunused-but-set-variable]
FP_DECL_D(A);
^
include/math-emu/double.h:73:23: note: expanded from macro 'FP_DECL_D'
#define FP_DECL_D(X) _FP_DECL(2,X)
^
include/math-emu/op-common.h:28:14: note: expanded from macro '_FP_DECL'
_FP_I_TYPE X##_c=0, X##_s=0, X##_e=0; \
^
<scratch space>:124:1: note: expanded from here
A_c
^
>> arch/powerpc/math-emu/fcmpu.c:14:2: warning: variable 'B_c' set but not used [-Wunused-but-set-variable]
FP_DECL_D(B);
^
include/math-emu/double.h:73:23: note: expanded from macro 'FP_DECL_D'
#define FP_DECL_D(X) _FP_DECL(2,X)
^
include/math-emu/op-common.h:28:14: note: expanded from macro '_FP_DECL'
_FP_I_TYPE X##_c=0, X##_s=0, X##_e=0; \
^
<scratch space>:130:1: note: expanded from here
B_c
^
>> arch/powerpc/math-emu/fcmpu.c:15:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
FP_DECL_EX;
^
include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
#define FP_DECL_EX int _fex = 0
^
arch/powerpc/math-emu/fcmpu.c:11:1: warning: no previous prototype for function 'fcmpu' [-Wmissing-prototypes]
fcmpu(u32 *ccr, int crfD, void *frA, void *frB)
^
arch/powerpc/math-emu/fcmpu.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
int
^
static
4 warnings generated.
--
>> arch/powerpc/math-emu/fctiw.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
FP_DECL_EX;
^
include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
#define FP_DECL_EX int _fex = 0
^
arch/powerpc/math-emu/fctiw.c:11:1: warning: no previous prototype for function 'fctiw' [-Wmissing-prototypes]
fctiw(u32 *frD, void *frB)
^
arch/powerpc/math-emu/fctiw.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
int
^
static
2 warnings generated.
--
>> arch/powerpc/math-emu/fctiwz.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
FP_DECL_EX;
^
include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
#define FP_DECL_EX int _fex = 0
^
arch/powerpc/math-emu/fctiwz.c:11:1: warning: no previous prototype for function 'fctiwz' [-Wmissing-prototypes]
fctiwz(u32 *frD, void *frB)
^
arch/powerpc/math-emu/fctiwz.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
int
^
static
2 warnings generated.
--
>> arch/powerpc/math-emu/fsel.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
FP_DECL_EX;
^
include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
#define FP_DECL_EX int _fex = 0
^
arch/powerpc/math-emu/fsel.c:11:1: warning: no previous prototype for function 'fsel' [-Wmissing-prototypes]
fsel(u32 *frD, void *frA, u32 *frB, u32 *frC)
^
arch/powerpc/math-emu/fsel.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
int
^
static
2 warnings generated.
vim +/A_c +13 arch/powerpc/math-emu/fcmpu.c
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 9
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 10 int
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 11 fcmpu(u32 *ccr, int crfD, void *frA, void *frB)
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 12 {
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 @13 FP_DECL_D(A);
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 @14 FP_DECL_D(B);
d2b194ed820880 arch/powerpc/math-emu/fcmpu.c Kumar Gala 2008-06-04 @15 FP_DECL_EX;
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 16 int code[4] = { (1 << 3), (1 << 1), (1 << 2), (1 << 0) };
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 17 long cmp;
^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 18
:::::: The code at line 13 was first introduced by commit
:::::: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Linux-2.6.12-rc2
:::::: TO: Linus Torvalds <torvalds@ppc970.osdl.org>
:::::: CC: Linus Torvalds <torvalds@ppc970.osdl.org>
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used
2023-05-22 19:00 arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used kernel test robot
@ 2023-06-14 14:11 ` Christophe Leroy
2023-06-14 16:04 ` Nick Desaulniers
0 siblings, 1 reply; 5+ messages in thread
From: Christophe Leroy @ 2023-06-14 14:11 UTC (permalink / raw)
To: kernel test robot
Cc: llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev,
linux-kernel@vger.kernel.org, Michael Ellerman, Nathan Chancellor
Hi,
Le 22/05/2023 à 21:00, kernel test robot a écrit :
> Hi Christophe,
>
> FYI, the error/warning still remains.
>
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 44c026a73be8038f03dbdeef028b642880cf1511
> commit: 7245fc5bb7a966852d5bd7779d1f5855530b461a powerpc/math-emu: Remove -w build flag and fix warnings
> date: 9 months ago
> config: powerpc-randconfig-r022-20230522 (https://download.01.org/0day-ci/archive/20230523/202305230231.3Wb7Q68G-lkp@intel.com/config)
> compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project b0fb98227c90adf2536c9ad644a74d5e92961111)
> 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 powerpc cross compiling tool for clang build
> # apt-get install binutils-powerpc-linux-gnu
> # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7245fc5bb7a966852d5bd7779d1f5855530b461a
> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> git fetch --no-tags linus master
> git checkout 7245fc5bb7a966852d5bd7779d1f5855530b461a
> # save the config file
> mkdir build_dir && cp config build_dir/.config
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/math-emu/
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202305230231.3Wb7Q68G-lkp@intel.com/
>
> All warnings (new ones prefixed by >>):
>
>>> arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used [-Wunused-but-set-variable]
This code is imported, and there is no plan to make any change to it.
Can you desactivate that warning ?
Thanks
Christophe
> FP_DECL_D(A);
> ^
> include/math-emu/double.h:73:23: note: expanded from macro 'FP_DECL_D'
> #define FP_DECL_D(X) _FP_DECL(2,X)
> ^
> include/math-emu/op-common.h:28:14: note: expanded from macro '_FP_DECL'
> _FP_I_TYPE X##_c=0, X##_s=0, X##_e=0; \
> ^
> <scratch space>:124:1: note: expanded from here
> A_c
> ^
>>> arch/powerpc/math-emu/fcmpu.c:14:2: warning: variable 'B_c' set but not used [-Wunused-but-set-variable]
> FP_DECL_D(B);
> ^
> include/math-emu/double.h:73:23: note: expanded from macro 'FP_DECL_D'
> #define FP_DECL_D(X) _FP_DECL(2,X)
> ^
> include/math-emu/op-common.h:28:14: note: expanded from macro '_FP_DECL'
> _FP_I_TYPE X##_c=0, X##_s=0, X##_e=0; \
> ^
> <scratch space>:130:1: note: expanded from here
> B_c
> ^
>>> arch/powerpc/math-emu/fcmpu.c:15:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
> FP_DECL_EX;
> ^
> include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
> #define FP_DECL_EX int _fex = 0
> ^
> arch/powerpc/math-emu/fcmpu.c:11:1: warning: no previous prototype for function 'fcmpu' [-Wmissing-prototypes]
> fcmpu(u32 *ccr, int crfD, void *frA, void *frB)
> ^
> arch/powerpc/math-emu/fcmpu.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> int
> ^
> static
> 4 warnings generated.
> --
>>> arch/powerpc/math-emu/fctiw.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
> FP_DECL_EX;
> ^
> include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
> #define FP_DECL_EX int _fex = 0
> ^
> arch/powerpc/math-emu/fctiw.c:11:1: warning: no previous prototype for function 'fctiw' [-Wmissing-prototypes]
> fctiw(u32 *frD, void *frB)
> ^
> arch/powerpc/math-emu/fctiw.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> int
> ^
> static
> 2 warnings generated.
> --
>>> arch/powerpc/math-emu/fctiwz.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
> FP_DECL_EX;
> ^
> include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
> #define FP_DECL_EX int _fex = 0
> ^
> arch/powerpc/math-emu/fctiwz.c:11:1: warning: no previous prototype for function 'fctiwz' [-Wmissing-prototypes]
> fctiwz(u32 *frD, void *frB)
> ^
> arch/powerpc/math-emu/fctiwz.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> int
> ^
> static
> 2 warnings generated.
> --
>>> arch/powerpc/math-emu/fsel.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
> FP_DECL_EX;
> ^
> include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
> #define FP_DECL_EX int _fex = 0
> ^
> arch/powerpc/math-emu/fsel.c:11:1: warning: no previous prototype for function 'fsel' [-Wmissing-prototypes]
> fsel(u32 *frD, void *frA, u32 *frB, u32 *frC)
> ^
> arch/powerpc/math-emu/fsel.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> int
> ^
> static
> 2 warnings generated.
>
>
> vim +/A_c +13 arch/powerpc/math-emu/fcmpu.c
>
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 9
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 10 int
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 11 fcmpu(u32 *ccr, int crfD, void *frA, void *frB)
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 12 {
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 @13 FP_DECL_D(A);
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 @14 FP_DECL_D(B);
> d2b194ed820880 arch/powerpc/math-emu/fcmpu.c Kumar Gala 2008-06-04 @15 FP_DECL_EX;
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 16 int code[4] = { (1 << 3), (1 << 1), (1 << 2), (1 << 0) };
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 17 long cmp;
> ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 18
>
> :::::: The code at line 13 was first introduced by commit
> :::::: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Linux-2.6.12-rc2
>
> :::::: TO: Linus Torvalds <torvalds@ppc970.osdl.org>
> :::::: CC: Linus Torvalds <torvalds@ppc970.osdl.org>
>
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used
2023-06-14 14:11 ` Christophe Leroy
@ 2023-06-14 16:04 ` Nick Desaulniers
2023-06-14 18:26 ` Christophe Leroy
0 siblings, 1 reply; 5+ messages in thread
From: Nick Desaulniers @ 2023-06-14 16:04 UTC (permalink / raw)
To: Christophe Leroy
Cc: kernel test robot, llvm@lists.linux.dev,
oe-kbuild-all@lists.linux.dev, linux-kernel@vger.kernel.org,
Michael Ellerman, Nathan Chancellor
On Wed, Jun 14, 2023 at 10:11 AM Christophe Leroy
<christophe.leroy@csgroup.eu> wrote:
>
> Hi,
>
> Le 22/05/2023 à 21:00, kernel test robot a écrit :
> > Hi Christophe,
> >
> > FYI, the error/warning still remains.
> >
> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > head: 44c026a73be8038f03dbdeef028b642880cf1511
> > commit: 7245fc5bb7a966852d5bd7779d1f5855530b461a powerpc/math-emu: Remove -w build flag and fix warnings
> > date: 9 months ago
> > config: powerpc-randconfig-r022-20230522 (https://download.01.org/0day-ci/archive/20230523/202305230231.3Wb7Q68G-lkp@intel.com/config)
> > compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project b0fb98227c90adf2536c9ad644a74d5e92961111)
> > 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 powerpc cross compiling tool for clang build
> > # apt-get install binutils-powerpc-linux-gnu
> > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7245fc5bb7a966852d5bd7779d1f5855530b461a
> > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> > git fetch --no-tags linus master
> > git checkout 7245fc5bb7a966852d5bd7779d1f5855530b461a
> > # save the config file
> > mkdir build_dir && cp config build_dir/.config
> > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
> > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/math-emu/
> >
> > If you fix the issue, kindly add following tag where applicable
> > | Reported-by: kernel test robot <lkp@intel.com>
> > | Closes: https://lore.kernel.org/oe-kbuild-all/202305230231.3Wb7Q68G-lkp@intel.com/
> >
> > All warnings (new ones prefixed by >>):
> >
> >>> arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used [-Wunused-but-set-variable]
>
> This code is imported, and there is no plan to make any change to it.
> Can you desactivate that warning ?
If the code is imported, and we don't plan to push fixes upstream,
does it make sense to just set -Wno-unusued-but-set-variable in
arch/powerpc/math-emu/Makefile?
Wait, what?!
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/math-emu/Makefile#n20
arch/powerpc/math-emu/Makefile already has -Wunused-but-set-variable
in ccflags-remove-y. But if KBUILD_EXTRA_WARN is set for W=1 builds,
-Wunused-but-set-variable is added back, but only for math.o and
math_efp.o. The warning above comes from building fcmpu.o. So how
did -Wunused-but-set-variable get set in the first place?
commit 78c73c80fd86 ("powerpc/math-emu: Inhibit W=1 warnings")
seems to have cleaned up this code for W=1 with GCC. This report is a
result of W=1 with CC=clang.
>
> Thanks
> Christophe
>
> > FP_DECL_D(A);
> > ^
> > include/math-emu/double.h:73:23: note: expanded from macro 'FP_DECL_D'
> > #define FP_DECL_D(X) _FP_DECL(2,X)
> > ^
> > include/math-emu/op-common.h:28:14: note: expanded from macro '_FP_DECL'
> > _FP_I_TYPE X##_c=0, X##_s=0, X##_e=0; \
> > ^
> > <scratch space>:124:1: note: expanded from here
> > A_c
> > ^
> >>> arch/powerpc/math-emu/fcmpu.c:14:2: warning: variable 'B_c' set but not used [-Wunused-but-set-variable]
> > FP_DECL_D(B);
> > ^
> > include/math-emu/double.h:73:23: note: expanded from macro 'FP_DECL_D'
> > #define FP_DECL_D(X) _FP_DECL(2,X)
> > ^
> > include/math-emu/op-common.h:28:14: note: expanded from macro '_FP_DECL'
> > _FP_I_TYPE X##_c=0, X##_s=0, X##_e=0; \
> > ^
> > <scratch space>:130:1: note: expanded from here
> > B_c
> > ^
> >>> arch/powerpc/math-emu/fcmpu.c:15:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
> > FP_DECL_EX;
> > ^
> > include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
> > #define FP_DECL_EX int _fex = 0
> > ^
> > arch/powerpc/math-emu/fcmpu.c:11:1: warning: no previous prototype for function 'fcmpu' [-Wmissing-prototypes]
> > fcmpu(u32 *ccr, int crfD, void *frA, void *frB)
> > ^
> > arch/powerpc/math-emu/fcmpu.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> > int
> > ^
> > static
> > 4 warnings generated.
> > --
> >>> arch/powerpc/math-emu/fctiw.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
> > FP_DECL_EX;
> > ^
> > include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
> > #define FP_DECL_EX int _fex = 0
> > ^
> > arch/powerpc/math-emu/fctiw.c:11:1: warning: no previous prototype for function 'fctiw' [-Wmissing-prototypes]
> > fctiw(u32 *frD, void *frB)
> > ^
> > arch/powerpc/math-emu/fctiw.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> > int
> > ^
> > static
> > 2 warnings generated.
> > --
> >>> arch/powerpc/math-emu/fctiwz.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
> > FP_DECL_EX;
> > ^
> > include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
> > #define FP_DECL_EX int _fex = 0
> > ^
> > arch/powerpc/math-emu/fctiwz.c:11:1: warning: no previous prototype for function 'fctiwz' [-Wmissing-prototypes]
> > fctiwz(u32 *frD, void *frB)
> > ^
> > arch/powerpc/math-emu/fctiwz.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> > int
> > ^
> > static
> > 2 warnings generated.
> > --
> >>> arch/powerpc/math-emu/fsel.c:14:2: warning: variable '_fex' set but not used [-Wunused-but-set-variable]
> > FP_DECL_EX;
> > ^
> > include/math-emu/soft-fp.h:94:24: note: expanded from macro 'FP_DECL_EX'
> > #define FP_DECL_EX int _fex = 0
> > ^
> > arch/powerpc/math-emu/fsel.c:11:1: warning: no previous prototype for function 'fsel' [-Wmissing-prototypes]
> > fsel(u32 *frD, void *frA, u32 *frB, u32 *frC)
> > ^
> > arch/powerpc/math-emu/fsel.c:10:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
> > int
> > ^
> > static
> > 2 warnings generated.
> >
> >
> > vim +/A_c +13 arch/powerpc/math-emu/fcmpu.c
> >
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 9
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 10 int
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 11 fcmpu(u32 *ccr, int crfD, void *frA, void *frB)
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 12 {
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 @13 FP_DECL_D(A);
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 @14 FP_DECL_D(B);
> > d2b194ed820880 arch/powerpc/math-emu/fcmpu.c Kumar Gala 2008-06-04 @15 FP_DECL_EX;
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 16 int code[4] = { (1 << 3), (1 << 1), (1 << 2), (1 << 0) };
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 17 long cmp;
> > ^1da177e4c3f41 arch/ppc/math-emu/fcmpu.c Linus Torvalds 2005-04-16 18
> >
> > :::::: The code at line 13 was first introduced by commit
> > :::::: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Linux-2.6.12-rc2
> >
> > :::::: TO: Linus Torvalds <torvalds@ppc970.osdl.org>
> > :::::: CC: Linus Torvalds <torvalds@ppc970.osdl.org>
> >
--
Thanks,
~Nick Desaulniers
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used
2023-06-14 16:04 ` Nick Desaulniers
@ 2023-06-14 18:26 ` Christophe Leroy
2023-06-14 18:51 ` Nick Desaulniers
0 siblings, 1 reply; 5+ messages in thread
From: Christophe Leroy @ 2023-06-14 18:26 UTC (permalink / raw)
To: Nick Desaulniers
Cc: kernel test robot, llvm@lists.linux.dev,
oe-kbuild-all@lists.linux.dev, linux-kernel@vger.kernel.org,
Michael Ellerman, Nathan Chancellor
Le 14/06/2023 à 18:04, Nick Desaulniers a écrit :
> On Wed, Jun 14, 2023 at 10:11 AM Christophe Leroy
> <christophe.leroy@csgroup.eu> wrote:
>>
>> Hi,
>>
>> Le 22/05/2023 à 21:00, kernel test robot a écrit :
>>> Hi Christophe,
>>>
>>> FYI, the error/warning still remains.
>>>
>>> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
>>> head: 44c026a73be8038f03dbdeef028b642880cf1511
>>> commit: 7245fc5bb7a966852d5bd7779d1f5855530b461a powerpc/math-emu: Remove -w build flag and fix warnings
>>> date: 9 months ago
>>> config: powerpc-randconfig-r022-20230522 (https://download.01.org/0day-ci/archive/20230523/202305230231.3Wb7Q68G-lkp@intel.com/config)
>>> compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project b0fb98227c90adf2536c9ad644a74d5e92961111)
>>> 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 powerpc cross compiling tool for clang build
>>> # apt-get install binutils-powerpc-linux-gnu
>>> # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7245fc5bb7a966852d5bd7779d1f5855530b461a
>>> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
>>> git fetch --no-tags linus master
>>> git checkout 7245fc5bb7a966852d5bd7779d1f5855530b461a
>>> # save the config file
>>> mkdir build_dir && cp config build_dir/.config
>>> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
>>> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/math-emu/
>>>
>>> If you fix the issue, kindly add following tag where applicable
>>> | Reported-by: kernel test robot <lkp@intel.com>
>>> | Closes: https://lore.kernel.org/oe-kbuild-all/202305230231.3Wb7Q68G-lkp@intel.com/
>>>
>>> All warnings (new ones prefixed by >>):
>>>
>>>>> arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used [-Wunused-but-set-variable]
>>
>> This code is imported, and there is no plan to make any change to it.
>> Can you desactivate that warning ?
>
> If the code is imported, and we don't plan to push fixes upstream,
> does it make sense to just set -Wno-unusued-but-set-variable in
> arch/powerpc/math-emu/Makefile?
Yes, that's done already but clang ignores it apparently.
>
> Wait, what?!
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/math-emu/Makefile#n20
> arch/powerpc/math-emu/Makefile already has -Wunused-but-set-variable
> in ccflags-remove-y. But if KBUILD_EXTRA_WARN is set for W=1 builds,
> -Wunused-but-set-variable is added back, but only for math.o and
> math_efp.o. The warning above comes from building fcmpu.o. So how
> did -Wunused-but-set-variable get set in the first place?
Indeed.
I looked once more and found out that:
clang -Wp,-MMD,arch/powerpc/math-emu/.fcmpu.o.d -nostdinc
-I./arch/powerpc/include -I./arch/powerpc/include/generated -I./include
-I./arch/powerpc/include/uapi -I./arch/powerpc/include/generated/uapi
-I./include/uapi -I./include/generated/uapi -include
./include/linux/compiler-version.h -include ./include/linux/kconfig.h
-include ./include/linux/compiler_types.h -D__KERNEL__ -I ./arch/powerpc
-DHAVE_AS_ATHIGH=1 -fmacro-prefix-map=./= -Wundef -DKBUILD_EXTRA_WARN1
-Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs
-fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE
-Werror=implicit-function-declaration -Werror=implicit-int
-Werror=return-type -Wno-format-security -funsigned-char -std=gnu11
--target=powerpc64le-linux-gnu -fintegrated-as
-Werror=unknown-warning-option -Werror=ignored-optimization-argument
-Werror=option-ignored -Werror=unused-command-line-argument -mbig-endian
-m32 -msoft-float -pipe -mcpu=powerpc -mno-prefixed -mno-pcrel
-mno-altivec -mno-vsx -mno-mma -mno-spe -fno-asynchronous-unwind-tables
-mbig-endian -fno-delete-null-pointer-checks -Wno-frame-address
-Wno-address-of-packed-member -O2 -Wframe-larger-than=1024
-fno-stack-protector -Wno-gnu -Wno-unused-but-set-variable
-Wno-unused-const-variable -ftrivial-auto-var-init=zero
-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
-pg -Wdeclaration-after-statement -Wvla -Wno-pointer-sign
-Wcast-function-type -Wimplicit-fallthrough -fno-strict-overflow
-fno-stack-check -Werror=date-time -Werror=incompatible-pointer-types
-Wextra -Wunused -Wno-unused-parameter -Wmissing-format-attribute
-Wold-style-definition -Wmissing-include-dirs -Wunused-const-variable
-Wno-missing-field-initializers -Wno-sign-compare -Wno-type-limits
-Wno-shift-negative-value -g -Werror
-DKBUILD_MODFILE='"arch/powerpc/math-emu/fcmpu"'
-DKBUILD_BASENAME='"fcmpu"' -DKBUILD_MODNAME='"fcmpu"'
-D__KBUILD_MODNAME=kmod_fcmpu -c -o arch/powerpc/math-emu/fcmpu.o
arch/powerpc/math-emu/fcmpu.c ; ./tools/objtool/objtool --mcount
--uaccess --sec-address arch/powerpc/math-emu/fcmpu.o
If you move -Wunused before -Wno-unused-but-set-variable, then you don't
have the warning/error anymore. So what ? What the hell is clang
behaving that way ?
GCC documentation is explicit, see
https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html :
The combined effect of positive and negative forms is that more
specific options have priority over less specific ones, independently of
their position in the command-line.
Can clang be fixed ?
Christophe
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used
2023-06-14 18:26 ` Christophe Leroy
@ 2023-06-14 18:51 ` Nick Desaulniers
0 siblings, 0 replies; 5+ messages in thread
From: Nick Desaulniers @ 2023-06-14 18:51 UTC (permalink / raw)
To: Christophe Leroy
Cc: kernel test robot, llvm@lists.linux.dev,
oe-kbuild-all@lists.linux.dev, linux-kernel@vger.kernel.org,
Michael Ellerman, Nathan Chancellor
On Wed, Jun 14, 2023 at 2:26 PM Christophe Leroy
<christophe.leroy@csgroup.eu> wrote:
>
>
>
> Le 14/06/2023 à 18:04, Nick Desaulniers a écrit :
> > On Wed, Jun 14, 2023 at 10:11 AM Christophe Leroy
> > <christophe.leroy@csgroup.eu> wrote:
> >>
> >> Hi,
> >>
> >> Le 22/05/2023 à 21:00, kernel test robot a écrit :
> >>> Hi Christophe,
> >>>
> >>> FYI, the error/warning still remains.
> >>>
> >>> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> >>> head: 44c026a73be8038f03dbdeef028b642880cf1511
> >>> commit: 7245fc5bb7a966852d5bd7779d1f5855530b461a powerpc/math-emu: Remove -w build flag and fix warnings
> >>> date: 9 months ago
> >>> config: powerpc-randconfig-r022-20230522 (https://download.01.org/0day-ci/archive/20230523/202305230231.3Wb7Q68G-lkp@intel.com/config)
> >>> compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project b0fb98227c90adf2536c9ad644a74d5e92961111)
> >>> 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 powerpc cross compiling tool for clang build
> >>> # apt-get install binutils-powerpc-linux-gnu
> >>> # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7245fc5bb7a966852d5bd7779d1f5855530b461a
> >>> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> >>> git fetch --no-tags linus master
> >>> git checkout 7245fc5bb7a966852d5bd7779d1f5855530b461a
> >>> # save the config file
> >>> mkdir build_dir && cp config build_dir/.config
> >>> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
> >>> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/math-emu/
> >>>
> >>> If you fix the issue, kindly add following tag where applicable
> >>> | Reported-by: kernel test robot <lkp@intel.com>
> >>> | Closes: https://lore.kernel.org/oe-kbuild-all/202305230231.3Wb7Q68G-lkp@intel.com/
> >>>
> >>> All warnings (new ones prefixed by >>):
> >>>
> >>>>> arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used [-Wunused-but-set-variable]
> >>
> >> This code is imported, and there is no plan to make any change to it.
> >> Can you desactivate that warning ?
> >
> > If the code is imported, and we don't plan to push fixes upstream,
> > does it make sense to just set -Wno-unusued-but-set-variable in
> > arch/powerpc/math-emu/Makefile?
>
> Yes, that's done already but clang ignores it apparently.
>
> >
> > Wait, what?!
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/powerpc/math-emu/Makefile#n20
> > arch/powerpc/math-emu/Makefile already has -Wunused-but-set-variable
> > in ccflags-remove-y. But if KBUILD_EXTRA_WARN is set for W=1 builds,
> > -Wunused-but-set-variable is added back, but only for math.o and
> > math_efp.o. The warning above comes from building fcmpu.o. So how
> > did -Wunused-but-set-variable get set in the first place?
>
> Indeed.
>
> I looked once more and found out that:
>
> clang -Wp,-MMD,arch/powerpc/math-emu/.fcmpu.o.d -nostdinc
> -I./arch/powerpc/include -I./arch/powerpc/include/generated -I./include
> -I./arch/powerpc/include/uapi -I./arch/powerpc/include/generated/uapi
> -I./include/uapi -I./include/generated/uapi -include
> ./include/linux/compiler-version.h -include ./include/linux/kconfig.h
> -include ./include/linux/compiler_types.h -D__KERNEL__ -I ./arch/powerpc
> -DHAVE_AS_ATHIGH=1 -fmacro-prefix-map=./= -Wundef -DKBUILD_EXTRA_WARN1
> -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs
> -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE
> -Werror=implicit-function-declaration -Werror=implicit-int
> -Werror=return-type -Wno-format-security -funsigned-char -std=gnu11
> --target=powerpc64le-linux-gnu -fintegrated-as
> -Werror=unknown-warning-option -Werror=ignored-optimization-argument
> -Werror=option-ignored -Werror=unused-command-line-argument -mbig-endian
> -m32 -msoft-float -pipe -mcpu=powerpc -mno-prefixed -mno-pcrel
> -mno-altivec -mno-vsx -mno-mma -mno-spe -fno-asynchronous-unwind-tables
> -mbig-endian -fno-delete-null-pointer-checks -Wno-frame-address
> -Wno-address-of-packed-member -O2 -Wframe-larger-than=1024
> -fno-stack-protector -Wno-gnu -Wno-unused-but-set-variable
> -Wno-unused-const-variable -ftrivial-auto-var-init=zero
> -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
> -pg -Wdeclaration-after-statement -Wvla -Wno-pointer-sign
> -Wcast-function-type -Wimplicit-fallthrough -fno-strict-overflow
> -fno-stack-check -Werror=date-time -Werror=incompatible-pointer-types
> -Wextra -Wunused -Wno-unused-parameter -Wmissing-format-attribute
> -Wold-style-definition -Wmissing-include-dirs -Wunused-const-variable
> -Wno-missing-field-initializers -Wno-sign-compare -Wno-type-limits
> -Wno-shift-negative-value -g -Werror
> -DKBUILD_MODFILE='"arch/powerpc/math-emu/fcmpu"'
> -DKBUILD_BASENAME='"fcmpu"' -DKBUILD_MODNAME='"fcmpu"'
> -D__KBUILD_MODNAME=kmod_fcmpu -c -o arch/powerpc/math-emu/fcmpu.o
> arch/powerpc/math-emu/fcmpu.c ; ./tools/objtool/objtool --mcount
> --uaccess --sec-address arch/powerpc/math-emu/fcmpu.o
>
>
> If you move -Wunused before -Wno-unused-but-set-variable, then you don't
> have the warning/error anymore. So what ? What the hell is clang
> behaving that way ?
It's re-enabling ALL of the members of the -Wunused group without
having checked to see if any more specific members were already
disabled.
>
> GCC documentation is explicit, see
> https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html :
>
> The combined effect of positive and negative forms is that more
> specific options have priority over less specific ones, independently of
> their position in the command-line.
Ah, nice citation. I did not know that was the expected behavior of
this group diagnostics. Indeed, there's a behavior difference here.
https://godbolt.org/z/13MxqrjcW
>
> Can clang be fixed ?
Filed:
https://github.com/llvm/llvm-project/issues/63315
>
> Christophe
--
Thanks,
~Nick Desaulniers
^ permalink raw reply [flat|nested] 5+ messages in thread
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2023-05-22 19:00 arch/powerpc/math-emu/fcmpu.c:13:2: warning: variable 'A_c' set but not used kernel test robot
2023-06-14 14:11 ` Christophe Leroy
2023-06-14 16:04 ` Nick Desaulniers
2023-06-14 18:26 ` Christophe Leroy
2023-06-14 18:51 ` Nick Desaulniers
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