[v2] add more MISRA C rules to docs/misra/rules.rst

Commit Message

Stefano Stabellini June 10, 2022, 9:27 p.m. UTC

Add the new MISRA C rules agreed by the MISRA C working group to
docs/misra/rules.rst.

Signed-off-by: Stefano Stabellini <[e-mail]>
Reviewed-by: Bertrand Marquis <[e-mail]>
Acked-by: Julien Grall <[e-mail]>
Acked-by: Roger Pau Monné <[e-mail]>
---
Given the minimal/trivial changes I kept the acked/reviewed-by.

Changes in v2:
- use max_t/min_t instead of MAX/MIN in the Rule 5.3 example
- improve wording for the note of Rule 5.3
---
 docs/misra/rules.rst | 90 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)

Comments

Jan Beulich June 13, 2022, 7:36 a.m. UTC | #1

On 10.06.2022 23:27, Stefano Stabellini wrote:
> +   * - `Rule 5.3 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_05_03.c>`_
> +     - Required
> +     - An identifier declared in an inner scope shall not hide an
> +       identifier declared in an outer scope
> +     - Using macros as macro parameters at invocation time is allowed
> +       even if both macros use identically named local variables, e.g.
> +       max_t(var0, min_t(var1, var2))

Nit: I would have been okay with the prior use of MIN() and MAX() in this
example, but now that you have switched to min_t() / max_t() I think the
example also wants to match our macros of these names. Hence I'd like to
suggest that either you switch to using min() / max() (which also use
local variables), or you add the missing "type" arguments in both macro
invocations.

Jan

Stefano Stabellini June 13, 2022, 11:29 p.m. UTC | #2

On Mon, 13 Jun 2022, Jan Beulich wrote:
> On 10.06.2022 23:27, Stefano Stabellini wrote:
> > +   * - `Rule 5.3 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_05_03.c>`_
> > +     - Required
> > +     - An identifier declared in an inner scope shall not hide an
> > +       identifier declared in an outer scope
> > +     - Using macros as macro parameters at invocation time is allowed
> > +       even if both macros use identically named local variables, e.g.
> > +       max_t(var0, min_t(var1, var2))
> 
> Nit: I would have been okay with the prior use of MIN() and MAX() in this
> example, but now that you have switched to min_t() / max_t() I think the
> example also wants to match our macros of these names. Hence I'd like to
> suggest that either you switch to using min() / max() (which also use
> local variables), or you add the missing "type" arguments in both macro
> invocations.

I see your point. I'll use min/max as follows:

max(var0, min(var1, var2))

If you are OK with that and there are no other suggestions this tiny
change could be done on commit.

Jan Beulich June 14, 2022, 6:59 a.m. UTC | #3

On 14.06.2022 01:29, Stefano Stabellini wrote:
> On Mon, 13 Jun 2022, Jan Beulich wrote:
>> On 10.06.2022 23:27, Stefano Stabellini wrote:
>>> +   * - `Rule 5.3 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_05_03.c>`_
>>> +     - Required
>>> +     - An identifier declared in an inner scope shall not hide an
>>> +       identifier declared in an outer scope
>>> +     - Using macros as macro parameters at invocation time is allowed
>>> +       even if both macros use identically named local variables, e.g.
>>> +       max_t(var0, min_t(var1, var2))
>>
>> Nit: I would have been okay with the prior use of MIN() and MAX() in this
>> example, but now that you have switched to min_t() / max_t() I think the
>> example also wants to match our macros of these names. Hence I'd like to
>> suggest that either you switch to using min() / max() (which also use
>> local variables), or you add the missing "type" arguments in both macro
>> invocations.
> 
> I see your point. I'll use min/max as follows:
> 
> max(var0, min(var1, var2))
> 
> If you are OK with that and there are no other suggestions this tiny
> change could be done on commit.

Yes, that's fine with me.

Jan

Patch

diff --git a/docs/misra/rules.rst b/docs/misra/rules.rst
index 6ccff07765..c0bdc75987 100644
--- a/docs/misra/rules.rst
+++ b/docs/misra/rules.rst
@@ -89,6 +89,29 @@  existing codebase are work-in-progress.
        (xen/include/public/) are allowed to retain longer identifiers
        for backward compatibility.
 
+   * - `Rule 5.2 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_05_02.c>`_
+     - Required
+     - Identifiers declared in the same scope and name space shall be
+       distinct
+     - The Xen characters limit for identifiers is 40. Public headers
+       (xen/include/public/) are allowed to retain longer identifiers
+       for backward compatibility.
+
+   * - `Rule 5.3 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_05_03.c>`_
+     - Required
+     - An identifier declared in an inner scope shall not hide an
+       identifier declared in an outer scope
+     - Using macros as macro parameters at invocation time is allowed
+       even if both macros use identically named local variables, e.g.
+       max_t(var0, min_t(var1, var2))
+
+   * - `Rule 5.4 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_05_04.c>`_
+     - Required
+     - Macro identifiers shall be distinct
+     - The Xen characters limit for macro identifiers is 40. Public
+       headers (xen/include/public/) are allowed to retain longer
+       identifiers for backward compatibility.
+
    * - `Rule 6.2 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_06_02.c>`_
      - Required
      - Single-bit named bit fields shall not be of a signed type
@@ -123,8 +146,75 @@  existing codebase are work-in-progress.
        declarations of objects and functions that have internal linkage
      -
 
+   * - `Rule 8.10 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_08_10.c>`_
+     - Required
+     - An inline function shall be declared with the static storage class
+     - gnu_inline (without static) is allowed.
+
    * - `Rule 8.12 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_08_12.c>`_
      - Required
      - Within an enumerator list the value of an implicitly-specified
        enumeration constant shall be unique
      -
+
+   * - `Rule 9.1 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_09_01.c>`_
+     - Mandatory
+     - The value of an object with automatic storage duration shall not
+       be read before it has been set
+     - Rule clarification: do not use variables before they are
+       initialized. An explicit initializer is not necessarily required.
+       Try reducing the scope of the variable. If an explicit
+       initializer is added, consider initializing the variable to a
+       poison value.
+
+   * - `Rule 9.2 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_09_02.c>`_
+     - Required
+     - The initializer for an aggregate or union shall be enclosed in
+       braces
+     -
+
+   * - `Rule 13.6 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_13_06.c>`_
+     - Mandatory
+     - The operand of the sizeof operator shall not contain any
+       expression which has potential side effects
+     -
+
+   * - `Rule 14.1 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_14_01.c>`_
+     - Required
+     - A loop counter shall not have essentially floating type
+     -
+
+   * - `Rule 16.7 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_16_07.c>`_
+     - Required
+     - A switch-expression shall not have essentially Boolean type
+     -
+
+   * - `Rule 17.3 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_17_03.c>`_
+     - Mandatory
+     - A function shall not be declared implicitly
+     -
+
+   * - `Rule 17.4 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_17_04.c>`_
+     - Mandatory
+     - All exit paths from a function with non-void return type shall
+       have an explicit return statement with an expression
+     -
+
+   * - `Rule 20.7 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_20_07.c>`_
+     - Required
+     - Expressions resulting from the expansion of macro parameters
+       shall be enclosed in parentheses
+     -
+
+   * - `Rule 20.13 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_20_13.c>`_
+     - Required
+     - A line whose first token is # shall be a valid preprocessing
+       directive
+     -
+
+   * - `Rule 20.14 <https://gitlab.com/MISRA/MISRA-C/MISRA-C-2012/Example-Suite/-/blob/master/R_20_14.c>`_
+     - Required
+     - All #else #elif and #endif preprocessor directives shall reside
+       in the same file as the #if #ifdef or #ifndef directive to which
+       they are related
+     -