Re: [hnaz-linux-mm:master 380/523] arch/riscv/kernel/kgdb.c:47:5: warning: no previous prototype for 'decode_register_index'

[Vincent Chen <vincent.chen@sifive.com>]

On Wed, May 20, 2020 at 10:05 AM Andrew Morton
<akpm@linux-foundation.org> wrote:
>
> On Tue, 19 May 2020 16:44:22 +0800 kbuild test robot <lkp@intel.com> wrote:
>
> > Hi Andrew,
> >
> > First bad commit (maybe != root cause):
> >
> > tree:   https://github.com/hnaz/linux-mm master
> > head:   2bbf0589bfeb27800c730b76eacf34528eee5418
> > commit: 91cd0b1b65c463042fdeb4ab5ffcb64ae43179cf [380/523] linux-next-rejects
> > config: riscv-allyesconfig (attached as .config)
> > compiler: riscv64-linux-gcc (GCC) 9.3.0
> > reproduce:
> >         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> >         chmod +x ~/bin/make.cross
> >         git checkout 91cd0b1b65c463042fdeb4ab5ffcb64ae43179cf
> >         # save the attached .config to linux build tree
> >         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=riscv
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kbuild test robot <lkp@intel.com>
> >
> > All warnings (new ones prefixed by >>, old ones prefixed by <<):
> >
> > >> arch/riscv/kernel/kgdb.c:47:5: warning: no previous prototype for 'decode_register_index' [-Wmissing-prototypes]
> > 47 | int decode_register_index(unsigned long opcode, int offset)
> > |     ^~~~~~~~~~~~~~~~~~~~~
> > >> arch/riscv/kernel/kgdb.c:52:5: warning: no previous prototype for 'decode_register_index_short' [-Wmissing-prototypes]
> > 52 | int decode_register_index_short(unsigned long opcode, int offset)
> > |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> > >> arch/riscv/kernel/kgdb.c:58:5: warning: no previous prototype for 'get_step_address' [-Wmissing-prototypes]
> > 58 | int get_step_address(struct pt_regs *regs, unsigned long *next_addr)
> > |     ^~~~~~~~~~~~~~~~
> > >> arch/riscv/kernel/kgdb.c:139:5: warning: no previous prototype for 'do_single_step' [-Wmissing-prototypes]
> > 139 | int do_single_step(struct pt_regs *regs)
> > |     ^~~~~~~~~~~~~~
> > >> arch/riscv/kernel/kgdb.c:276:6: warning: no previous prototype for 'kgdb_arch_handle_qxfer_pkt' [-Wmissing-prototypes]
> > 276 | void kgdb_arch_handle_qxfer_pkt(char *remcom_in_buffer,
> > |      ^~~~~~~~~~~~~~~~~~~~~~~~~~
> > >> arch/riscv/kernel/kgdb.c:323:5: warning: no previous prototype for 'kgdb_riscv_kgdbbreak' [-Wmissing-prototypes]
> > 323 | int kgdb_riscv_kgdbbreak(unsigned long addr)
> > |     ^~~~~~~~~~~~~~~~~~~~
> > In file included from arch/riscv/include/asm/kgdb.h:109,
> > from include/linux/kgdb.h:20,
> > from arch/riscv/kernel/kgdb.c:9:
> > arch/riscv/include/asm/gdb_xml.h:7:19: warning: 'riscv_gdb_stub_feature' defined but not used [-Wunused-const-variable=]
> > 7 | static const char riscv_gdb_stub_feature[64] =
> > |                   ^~~~~~~~~~~~~~~~~~~~~~
>
> I doubt if linux-next-rejects caused this error - all that patch does
> is fix up a reject between linux-next patches and
> https://ozlabs.org/~akpm/mmotm/broken-out/riscv-support-debug_wx.patch
>
> I'm more suspecting that this error is due Vincent's e4f2aa5808fc9
> ("riscv: Add KGDB support") or 899dc734805df ("riscv: Use the XML
> target descriptions to report 3 system registers").
>
>

I tried to use the following commands to reproduce the above warning
messages, but I failed.
1. git clone https://github.com/hnaz/linux-mm
2. wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross
-O ~/bin/make.cross
3. chmod +x ~/bin/make.cross
4. cd linux-mm
5. git checkout 91cd0b1b65c463042fdeb4ab5ffcb64ae43179cf
6. make ARCH=riscv allyesconfig
7. COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=riscv

Could you help me correct the reproduce steps?

Thank you.