RE: [PATCH -next] ACPICA: Make acpi_protocol_lengths static

[Kaneda, Erik]

> -----Original Message-----
> From: linux-acpi-owner@xxxxxxxxxxxxxxx <linux-acpi-
> owner@xxxxxxxxxxxxxxx> On Behalf Of Yuehaibing
> Sent: Monday, March 30, 2020 8:29 PM
> To: Kaneda, Erik <erik.kaneda@xxxxxxxxx>; Rafael J. Wysocki
> <rafael@xxxxxxxxxx>; Moore, Robert <robert.moore@xxxxxxxxx>
> Cc: Wysocki, Rafael J <rafael.j.wysocki@xxxxxxxxx>; Len Brown
> <lenb@xxxxxxxxxx>; ACPI Devel Maling List <linux-acpi@xxxxxxxxxxxxxxx>;
> open list:ACPI COMPONENT ARCHITECTURE (ACPICA) <devel@xxxxxxxxxx>;
> Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx>
> Subject: Re: [PATCH -next] ACPICA: Make acpi_protocol_lengths static
> 
> On 2020/3/31 1:52, Kaneda, Erik wrote:
> >
> >
> >> -----Original Message-----
> >> From: linux-acpi-owner@xxxxxxxxxxxxxxx <linux-acpi-
> >> owner@xxxxxxxxxxxxxxx> On Behalf Of Rafael J. Wysocki
> >> Sent: Saturday, March 28, 2020 2:14 AM
> >> To: YueHaibing <yuehaibing@xxxxxxxxxx>; Moore, Robert
> >> <robert.moore@xxxxxxxxx>; Kaneda, Erik <erik.kaneda@xxxxxxxxx>
> >> Cc: Wysocki, Rafael J <rafael.j.wysocki@xxxxxxxxx>; Len Brown
> >> <lenb@xxxxxxxxxx>; ACPI Devel Maling List
> >> <linux-acpi@xxxxxxxxxxxxxxx>; open list:ACPI COMPONENT
> ARCHITECTURE
> >> (ACPICA) <devel@xxxxxxxxxx>; Linux Kernel Mailing List
> >> <linux-kernel@xxxxxxxxxxxxxxx>
> >> Subject: Re: [PATCH -next] ACPICA: Make acpi_protocol_lengths static
> >>
> >> On Sat, Mar 28, 2020 at 4:47 AM YueHaibing <yuehaibing@xxxxxxxxxx>
> >> wrote:
> >>>
> >>> Fix sparse warning:
> >>>
> >>> drivers/acpi/acpica/exfield.c:25:10: warning:
> >>>  symbol 'acpi_protocol_lengths' was not declared. Should it be static?
> >
> > I donât understand what sparse is trying to say here. This variable is
> declared in exfield.c...
> > Could you provide more details on this sparse warning?
> 
> This is sparse -Wdel option's job, see man manual:
> 
>        -Wdecl Warn about any non-static variable or function definition that
>               has no previous declaration.
> 
>               Private symbols (functions and variables) internal to a given
>               source file should use static, to allow additional compiler
>               optimizations, allow detection of unused symbols, and prevent
>               other code from relying on these internal symbols.  Public
>               symbols used by other source files will need declarations
>               visible to those other source files, such as in a header file.
>               All declarations should fall into one of these two categories.
>               Thus, with -Wdecl, Sparse warns about any symbol definition
>               with neither static nor a declaration.  To fix this warning,
>               declare private symbols static, and ensure that the files
>               defining public symbols have the symbol declarations available
>               first (such as by including the appropriate header file).

Thanks for the info. I made a pull request to ACPICA codebase here: https://github.com/acpica/acpica/pull/581
I will send this to Linux upstream after the next ACPICA release (toward the end of this month)

Thanks,
Erik
> 
> >
> > Erik
> >
> >>>
> >>> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
> >>
> >> Bob, Erik, I'm leaving this one to you.
> >>
> >>> ---
> >>>  drivers/acpi/acpica/exfield.c | 2 +-
> >>>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>>
> >>> diff --git a/drivers/acpi/acpica/exfield.c
> >>> b/drivers/acpi/acpica/exfield.c index e85eb31e5075..3323a2ba6a31
> >>> 100644
> >>> --- a/drivers/acpi/acpica/exfield.c
> >>> +++ b/drivers/acpi/acpica/exfield.c
> >>> @@ -22,7 +22,7 @@ ACPI_MODULE_NAME("exfield")
> >>>   */
> >>>  #define ACPI_INVALID_PROTOCOL_ID        0x80
> >>>  #define ACPI_MAX_PROTOCOL_ID            0x0F
> >>> -const u8 acpi_protocol_lengths[] = {
> >>> +static const u8 acpi_protocol_lengths[] = {
> >>>         ACPI_INVALID_PROTOCOL_ID,       /* 0 - reserved */
> >>>         ACPI_INVALID_PROTOCOL_ID,       /* 1 - reserved */
> >>>         0x00,                   /* 2 - ATTRIB_QUICK */
> >>> --
> >>> 2.17.1
> >>>
> >>>