2017-07-04 19:29:25

by Heinrich Schuchardt

[permalink] [raw]
Subject: [BUG] checkpatch: false positive storage class location

The U-Boot project uses the same scripts/checkpatch.pl as the Linux
kernel. I ran upon the problem below when working on U-Boot. But I
guess it should be fixed in the Linux upstream.

Running checkpatch for this email produces
WARNING: storage class should be at the beginning of the declaration

This relates to the parameter with asmlinkage.

asmlinkage is at the start of the parameter so I think this a false
positive.

Signed-off-by: Heinrich.Schuchardt <[email protected]>
---

cmd/bootefi.c | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/cmd/bootefi.c b/cmd/bootefi.c
index 771300ee94..4df468307c 100644
--- a/cmd/bootefi.c
+++ b/cmd/bootefi.c
@@ -147,6 +147,12 @@ static void *copy_fdt(void *fdt)
return new_fdt;
}

+static ulong efi_do_enter(void *image_handle,
+ struct efi_system_table *st, asmlinkage ulong (*entry)(
+ void *image_handle, struct efi_system_table *st))
+{
+ return 0;
+}
+
/*
end
*/
--
2.11.0


2017-07-04 20:44:28

by Joe Perches

[permalink] [raw]
Subject: Re: [BUG] checkpatch: false positive storage class location

On Tue, 2017-07-04 at 21:29 +0200, Heinrich Schuchardt wrote:
> The U-Boot project uses the same scripts/checkpatch.pl as the Linux
> kernel. I ran upon the problem below when working on U-Boot. But I
> guess it should be fixed in the Linux upstream.
>
> Running checkpatch for this email produces
> WARNING: storage class should be at the beginning of the declaration
>
> This relates to the parameter with asmlinkage.
>
> asmlinkage is at the start of the parameter so I think this a false
> positive.
>
> Signed-off-by: Heinrich.Schuchardt <[email protected]>
> ---
>
> cmd/bootefi.c | 22 +++++++++++++++++-----
> 1 file changed, 17 insertions(+), 5 deletions(-)
>
> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
> index 771300ee94..4df468307c 100644
> --- a/cmd/bootefi.c
> +++ b/cmd/bootefi.c
> @@ -147,6 +147,12 @@ static void *copy_fdt(void *fdt)
> return new_fdt;
> }
>
> +static ulong efi_do_enter(void *image_handle,
> + struct efi_system_table *st, asmlinkage ulong (*entry)(
> + void *image_handle, struct efi_system_table *st))
> +{
> + return 0;
> +}
> +
> /*
> end
> */

Perhaps this?
-------------------------

Allow storage class after comma for function pointers.

Miscellanea:

o Add missing semicolon after WARN statement
---
scripts/checkpatch.pl | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 43171ed88115..c7490ab48ce1 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5577,9 +5577,10 @@ sub process {
}

# Check that the storage class is at the beginning of a declaration
- if ($line =~ /\b$Storage\b/ && $line !~ /^.\s*$Storage\b/) {
+ if ($line =~ /\b$Storage\b/ &&
+ $line !~ /^.\s*(?:.*,\s*)?$Storage\b/) {
WARN("STORAGE_CLASS",
- "storage class should be at the beginning of the declaration\n" . $herecurr)
+ "storage class should be at the beginning of the declaration\n" . $herecurr);
}

# check the location of the inline attribute, that it is between

2017-07-04 21:08:33

by Heinrich Schuchardt

[permalink] [raw]
Subject: Re: [BUG] checkpatch: false positive storage class location

On 07/04/2017 10:44 PM, Joe Perches wrote:
> On Tue, 2017-07-04 at 21:29 +0200, Heinrich Schuchardt wrote:
>> The U-Boot project uses the same scripts/checkpatch.pl as the Linux
>> kernel. I ran upon the problem below when working on U-Boot. But I
>> guess it should be fixed in the Linux upstream.
>>
>> Running checkpatch for this email produces
>> WARNING: storage class should be at the beginning of the declaration
>>
>> This relates to the parameter with asmlinkage.
>>
>> asmlinkage is at the start of the parameter so I think this a false
>> positive.
>>
>> Signed-off-by: Heinrich.Schuchardt <[email protected]>
>> ---
>>
>> cmd/bootefi.c | 22 +++++++++++++++++-----
>> 1 file changed, 17 insertions(+), 5 deletions(-)
>>
>> diff --git a/cmd/bootefi.c b/cmd/bootefi.c
>> index 771300ee94..4df468307c 100644
>> --- a/cmd/bootefi.c
>> +++ b/cmd/bootefi.c
>> @@ -147,6 +147,12 @@ static void *copy_fdt(void *fdt)
>> return new_fdt;
>> }
>>
>> +static ulong efi_do_enter(void *image_handle,
>> + struct efi_system_table *st, asmlinkage ulong (*entry)(
>> + void *image_handle, struct efi_system_table *st))
>> +{
>> + return 0;
>> +}
>> +
>> /*
>> end
>> */
>
> Perhaps this?
> -------------------------
>
> Allow storage class after comma for function pointers.
>
> Miscellanea:
>
> o Add missing semicolon after WARN statement
> ---
> scripts/checkpatch.pl | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 43171ed88115..c7490ab48ce1 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -5577,9 +5577,10 @@ sub process {
> }
>
> # Check that the storage class is at the beginning of a declaration
> - if ($line =~ /\b$Storage\b/ && $line !~ /^.\s*$Storage\b/) {
> + if ($line =~ /\b$Storage\b/ &&
> + $line !~ /^.\s*(?:.*,\s*)?$Storage\b/) {
> WARN("STORAGE_CLASS",
> - "storage class should be at the beginning of the declaration\n" . $herecurr)
> + "storage class should be at the beginning of the declaration\n" . $herecurr);
> }
>
> # check the location of the inline attribute, that it is between
>

Thank you. This works for all cases but

+static ulong efi_do_enter(ulong asmlinkage (*entry)(void *image_handle,
+ struct efi_system_table *st))
+{
+ return 0;
+}
+

Here I get
WARNING: space prohibited between function name and open parenthesis '('
where I would have expected
WARNING: storage class should be at the beginning of the declaration

Best regards

Heinrich Schuchardt

2017-07-05 12:01:50

by Joe Perches

[permalink] [raw]
Subject: Re: [BUG] checkpatch: false positive storage class location

On Tue, 2017-07-04 at 23:08 +0200, Heinrich Schuchardt wrote:
> On 07/04/2017 10:44 PM, Joe Perches wrote:
> > On Tue, 2017-07-04 at 21:29 +0200, Heinrich Schuchardt wrote:
> > > The U-Boot project uses the same scripts/checkpatch.pl as the Linux
> > > kernel. I ran upon the problem below when working on U-Boot. But I
> > > guess it should be fixed in the Linux upstream.
> > >
> > > Running checkpatch for this email produces
> > > WARNING: storage class should be at the beginning of the declaration
> > >
> > > This relates to the parameter with asmlinkage.
> > >
> > > asmlinkage is at the start of the parameter so I think this a false
> > > positive.
> > >
> > > Signed-off-by: Heinrich.Schuchardt <[email protected]>
> > > ---
> > >
> > > cmd/bootefi.c | 22 +++++++++++++++++-----
> > > 1 file changed, 17 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/cmd/bootefi.c b/cmd/bootefi.c
> > > index 771300ee94..4df468307c 100644
> > > --- a/cmd/bootefi.c
> > > +++ b/cmd/bootefi.c
> > > @@ -147,6 +147,12 @@ static void *copy_fdt(void *fdt)
> > > return new_fdt;
> > > }
> > >
> > > +static ulong efi_do_enter(void *image_handle,
> > > + struct efi_system_table *st, asmlinkage ulong (*entry)(
> > > + void *image_handle, struct efi_system_table *st))
> > > +{
> > > + return 0;
> > > +}
> > > +
> > > /*
> > > end
> > > */
> >
> > Perhaps this?
> > -------------------------
> >
> > Allow storage class after comma for function pointers.
> >
> > Miscellanea:
> >
> > o Add missing semicolon after WARN statement
> > ---
> > scripts/checkpatch.pl | 5 +++--
> > 1 file changed, 3 insertions(+), 2 deletions(-)
> >
> > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> > index 43171ed88115..c7490ab48ce1 100755
> > --- a/scripts/checkpatch.pl
> > +++ b/scripts/checkpatch.pl
> > @@ -5577,9 +5577,10 @@ sub process {
> > }
> >
> > # Check that the storage class is at the beginning of a declaration
> > - if ($line =~ /\b$Storage\b/ && $line !~ /^.\s*$Storage\b/) {
> > + if ($line =~ /\b$Storage\b/ &&
> > + $line !~ /^.\s*(?:.*,\s*)?$Storage\b/) {
> > WARN("STORAGE_CLASS",
> > - "storage class should be at the beginning of the declaration\n" . $herecurr)
> > + "storage class should be at the beginning of the declaration\n" . $herecurr);
> > }
> >
> > # check the location of the inline attribute, that it is between
> >
>
> Thank you. This works for all cases but
>
> +static ulong efi_do_enter(ulong asmlinkage (*entry)(void *image_handle,
> + struct efi_system_table *st))
> +{
> + return 0;
> +}
> +
>
> Here I get
> WARNING: space prohibited between function name and open parenthesis '('
> where I would have expected
> WARNING: storage class should be at the beginning of the declaration

checkpatch is and always will be a stupid brainless
little script based on a collection of regexes.

It won't get everything correct.

Your example has static as the first entry on the line.
static is a "$Storage" so it is at the beginning of the
declaration.

This particular declaration has a function pointer
as one of its arguments.

I do wonder if asmlinkage is even appropriate as part of
that function pointer argument.

Anyway, maybe this:
---
scripts/checkpatch.pl | 12 ++++++++++--
?1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 43171ed88115..21bb6814f8bb 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5576,10 +5576,18 @@ sub process {
? "architecture specific defines should be avoided\n" . $herecurr);
? }
?
+# check that the storage class is not after a type
+ if ($line =~ /\b($Type)\s+($Storage)\b/) {
+ WARN("STORAGE_CLASS",
+ "storage class '$2' should be located before type '$1'\n" . $herecurr);
+ }
?# Check that the storage class is at the beginning of a declaration
- if ($line =~ /\b$Storage\b/ && $line !~ /^.\s*$Storage\b/) {
+ if ($line =~ /\b$Storage\b/ &&
+ $line !~ /^.\s*$Storage/ &&
+ $line =~ /^.\s*(.+?)\$Storage\s/ &&
+ $1 !~ /[\,\)]\s*$/) {
? WARN("STORAGE_CLASS",
- "storage class should be at the beginning of the declaration\n" . $herecurr)
+ "storage class should be at the beginning of the declaration\n" . $herecurr);
? }
?
?# check the location of the inline attribute, that it is between