Re: [PATCH] riscv: asm/gdb_xml.h: use __maybe_used to make W=1 warnings go away

From: Vincent Chen
Date: Wed Jul 01 2020 - 22:05:06 EST


On Thu, Jul 2, 2020 at 2:48 AM Pierre-Louis Bossart
<pierre-louis.bossart@xxxxxxxxxxxxxxx> wrote:
>
> 0day/kbuild reports warnings with the ASoC codecs compiled with W=1.
>
> In file included from arch/riscv/include/asm/kgdb.h:109,
> from include/linux/kgdb.h:20,
> from include/linux/fb.h:5,
> from include/drm/drm_crtc.h:31,
> from sound/soc/codecs/hdmi-codec.c:19:
>
> arch/riscv/include/asm/gdb_xml.h:23:19: warning:
> 'riscv_gdb_stub_cpuxml' defined but not used [-Wunused-const-variable=]
> 23 | static const char riscv_gdb_stub_cpuxml[2048] =
> | ^~~~~~~~~~~~~~~~~~~~~
> arch/riscv/include/asm/gdb_xml.h:16:19: warning:
> 'riscv_gdb_stub_target_desc' defined but not used [-Wunused-const-variable=]
> 16 | static const char riscv_gdb_stub_target_desc[256] =
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~
> arch/riscv/include/asm/gdb_xml.h:13:19: warning:
> 'gdb_xfer_read_cpuxml' defined but not used [-Wunused-const-variable=]
> 13 | static const char gdb_xfer_read_cpuxml[39] =
> | ^~~~~~~~~~~~~~~~~~~~
> arch/riscv/include/asm/gdb_xml.h:10:19: warning:
> 'gdb_xfer_read_target' defined but not used [-Wunused-const-variable=]
> 10 | static const char gdb_xfer_read_target[31] = "qXfer:features:read:target.xml:";
> | ^~~~~~~~~~~~~~~~~~~~
> 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] =
> | ^~~~~~~~~~~~~~~~~~~~~~
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
> ---
>
> I don't know if this is the right way of solving this issue but this
> error is now consistently thrown in kbuild compile-test reports w/
> W=1.
>

Dear Pierre-Louis Bossart:
Thanks for your modifications. I have fixed the warnings in my latest
KGDB patchset and sent it out, but the merged KGDB patchset is not my
latest version.
I have sent a patch set to complement the missing ports, and I think
these warnings would disappear after this patch has been accepted and
merged.

Here is the patch to fix this warning:
http://lists.infradead.org/pipermail/linux-riscv/2020-June/000660.html


> arch/riscv/include/asm/gdb_xml.h | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/arch/riscv/include/asm/gdb_xml.h b/arch/riscv/include/asm/gdb_xml.h
> index 041b45f5b997..c28fc1a1d230 100644
> --- a/arch/riscv/include/asm/gdb_xml.h
> +++ b/arch/riscv/include/asm/gdb_xml.h
> @@ -4,23 +4,23 @@
> #define __ASM_GDB_XML_H_
>
> #define kgdb_arch_gdb_stub_feature riscv_gdb_stub_feature
> -static const char riscv_gdb_stub_feature[64] =
> +static __maybe_unused const char riscv_gdb_stub_feature[64] =
> "PacketSize=800;qXfer:features:read+;";
>
> -static const char gdb_xfer_read_target[31] = "qXfer:features:read:target.xml:";
> +static __maybe_unused const char gdb_xfer_read_target[31] = "qXfer:features:read:target.xml:";
>
> #ifdef CONFIG_64BIT
> -static const char gdb_xfer_read_cpuxml[39] =
> +static __maybe_unused const char gdb_xfer_read_cpuxml[39] =
> "qXfer:features:read:riscv-64bit-cpu.xml";
>
> -static const char riscv_gdb_stub_target_desc[256] =
> +static __maybe_unused const char riscv_gdb_stub_target_desc[256] =
> "l<?xml version=\"1.0\"?>"
> "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
> "<target>"
> "<xi:include href=\"riscv-64bit-cpu.xml\"/>"
> "</target>";
>
> -static const char riscv_gdb_stub_cpuxml[2048] =
> +static __maybe_unused const char riscv_gdb_stub_cpuxml[2048] =
> "l<?xml version=\"1.0\"?>"
> "<!DOCTYPE feature SYSTEM \"gdb-target.dtd\">"
> "<feature name=\"org.gnu.gdb.riscv.cpu\">"
> --
> 2.25.1
>