Re: struct mctelem_cookie missing definition

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Fri, 14 Feb 2025, Jan Beulich wrote:
> > Would deviating macros "COOKIE2MCTE" and "MCTE2COOKIE" work?
> 
> If it did, COOKIE2ID and ID2COOKIE would likely need including as well.

I wrote this patch. Nicola, can you please check the changes to
deviations.ecl, this is the first time I try to write the deviation
myself :-)

---
misra: add 11.2 deviation for incomplete types

struct mctelem_cookie* is used exactly because it is an incomplete type
so the pointer cannot be dereferenced. This is deliberate. So add a
deviation for it.

In deviations.ecl, add the list of macros that do the conversions to and
from struct mctelem_cookie*.

Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxx>

diff --git a/automation/eclair_analysis/ECLAIR/deviations.ecl 
b/automation/eclair_analysis/ECLAIR/deviations.ecl
index a28eb0ae76..87bfd2160c 100644
--- a/automation/eclair_analysis/ECLAIR/deviations.ecl
+++ b/automation/eclair_analysis/ECLAIR/deviations.ecl
@@ -366,6 +366,14 @@ constant expressions are required.\""
 }
 -doc_end
 
+-doc_begin="Certain pointers point to incomplete types purposely so that they 
are impossible to dereference."
+-config=MC3A2.R11.2,reports+={deliberate, 
"any_area(any_loc(any_exp(macro(^COOKIE2MCTE$))))"}
+-config=MC3A2.R11.2,reports+={deliberate, 
"any_area(any_loc(any_exp(macro(^MCTE2COOKIE$))))"}
+-config=MC3A2.R11.2,reports+={deliberate, 
"any_area(any_loc(any_exp(macro(^COOKIE2ID$))))"}
+-config=MC3A2.R11.2,reports+={deliberate, 
"any_area(any_loc(any_exp(macro(^ID2COOKIE$))))"}
+}
+-doc_end
+
 -doc_begin="Conversions to object pointers that have a pointee type with a 
smaller (i.e., less strict) alignment requirement are safe."
 -config=MC3A2.R11.3,casts+={safe,
   "!relation(more_aligned_pointee)"
diff --git a/docs/misra/deviations.rst b/docs/misra/deviations.rst
index fe0b1e10a2..f3004d6023 100644
--- a/docs/misra/deviations.rst
+++ b/docs/misra/deviations.rst
@@ -324,6 +324,12 @@ Deviations related to MISRA C:2012 Rules:
        semantics that do not lead to unexpected behaviour.
      - Tagged as `safe` for ECLAIR.
 
+   * - R11.2
+     - Certain pointers point to incomplete types purposely so that they
+       are impossible to dereference.
+     - Tagged as `deliberate` for ECLAIR. Such pointer is struct
+       mctelem_cookie \*.
+
    * - R11.2
      - The conversion from a pointer to an incomplete type to unsigned long
        does not lose any information, provided that the target type has enough