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[XEN PATCH v4] automation/eclair: extend existing deviations of MISRA C Rule 16.3

Federico Serafini posted 1 patch 2 months, 2 weeks ago
Patches applied successfully (tree, apply log)
git fetch https://gitlab.com/xen-project/patchew/xen tags/patchew/90044547484dac6fcb4748ae8758e38234b3261a.1719297249.git.federico.serafini@bugseng.com
There is a newer version of this series
.../eclair_analysis/ECLAIR/deviations.ecl     | 31 ++++++++++++++-----
automation/eclair_analysis/ECLAIR/tagging.ecl |  2 +-
docs/misra/deviations.rst                     | 28 +++++++++++++++--
3 files changed, 49 insertions(+), 12 deletions(-)
[XEN PATCH v4] automation/eclair: extend existing deviations of MISRA C Rule 16.3
Posted by Federico Serafini 2 months, 2 weeks ago 
Update ECLAIR configuration to deviate more cases where an
unintentional fallthrough cannot happen.

Tag Rule 16.3 as clean for arm.

Signed-off-by: Federico Serafini <federico.serafini@bugseng.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
Changes from v3:
- do not add the rule to the monitored set (it is already there).
---
Changes from v2:
- fixed grammar;
- reprhased deviations regarding do-while-false and ASSERT_UNREACHABLE().
---
 .../eclair_analysis/ECLAIR/deviations.ecl     | 31 ++++++++++++++-----
 automation/eclair_analysis/ECLAIR/tagging.ecl |  2 +-
 docs/misra/deviations.rst                     | 28 +++++++++++++++--
 3 files changed, 49 insertions(+), 12 deletions(-)

diff --git a/automation/eclair_analysis/ECLAIR/deviations.ecl b/automation/eclair_analysis/ECLAIR/deviations.ecl
index ae2eaf50f7..c8bff0e057 100644
--- a/automation/eclair_analysis/ECLAIR/deviations.ecl
+++ b/automation/eclair_analysis/ECLAIR/deviations.ecl
@@ -380,14 +380,30 @@ therefore it is deemed better to leave such files as is."
 -config=MC3R1.R16.2,reports+={deliberate, "any_area(any_loc(file(x86_emulate||x86_svm_emulate)))"}
 -doc_end
 
--doc_begin="Switch clauses ending with continue, goto, return statements are
-safe."
--config=MC3R1.R16.3,terminals+={safe, "node(continue_stmt||goto_stmt||return_stmt)"}
+-doc_begin="Statements that change the control flow (i.e., break, continue, goto, return) and calls to functions that do not return the control back are \"allowed terminal statements\"."
+-stmt_selector+={r16_3_allowed_terminal, "node(break_stmt||continue_stmt||goto_stmt||return_stmt)||call(property(noreturn))"}
+-config=MC3R1.R16.3,terminals+={safe, "r16_3_allowed_terminal"}
+-doc_end
+
+-doc_begin="An if-else statement having both branches ending with an allowed terminal statement is itself an allowed terminal statement."
+-stmt_selector+={r16_3_if, "node(if_stmt)&&(child(then,r16_3_allowed_terminal)||child(then,any_stmt(stmt,-1,r16_3_allowed_terminal)))"}
+-stmt_selector+={r16_3_else, "node(if_stmt)&&(child(else,r16_3_allowed_terminal)||child(else,any_stmt(stmt,-1,r16_3_allowed_terminal)))"}
+-stmt_selector+={r16_3_if_else, "r16_3_if&&r16_3_else"}
+-config=MC3R1.R16.3,terminals+={safe, "r16_3_if_else"}
+-doc_end
+
+-doc_begin="An if-else statement having an always true condition and the true branch ending with an allowed terminal statement is itself an allowed terminal statement."
+-stmt_selector+={r16_3_if_true, "r16_3_if&&child(cond,definitely_in(1..))"}
+-config=MC3R1.R16.3,terminals+={safe, "r16_3_if_true"}
+-doc_end
+
+-doc_begin="A switch clause ending with a statement expression which, in turn, ends with an allowed terminal statement is safe."
+-config=MC3R1.R16.3,terminals+={safe, "node(stmt_expr)&&child(stmt,node(compound_stmt)&&any_stmt(stmt,-1,r16_3_allowed_terminal||r16_3_if_else||r16_3_if_true))"}
 -doc_end
 
--doc_begin="Switch clauses ending with a call to a function that does not give
-the control back (i.e., a function with attribute noreturn) are safe."
--config=MC3R1.R16.3,terminals+={safe, "call(property(noreturn))"}
+-doc_begin="A switch clause ending with a do-while-false the body of which, in turn, ends with an allowed terminal statement is safe.
+An exception to that is the macro ASSERT_UNREACHABLE() which is effective in debug build only: a switch clause ending with ASSERT_UNREACHABLE() is not considered safe."
+-config=MC3R1.R16.3,terminals+={safe, "!macro(name(ASSERT_UNREACHABLE))&&node(do_stmt)&&child(cond,definitely_in(0))&&child(body,any_stmt(stmt,-1,r16_3_allowed_terminal||r16_3_if_else||r16_3_if_true))"}
 -doc_end
 
 -doc_begin="Switch clauses ending with pseudo-keyword \"fallthrough\" are
@@ -399,8 +415,7 @@ safe."
 -config=MC3R1.R16.3,reports+={safe, "any_area(end_loc(any_exp(text(/BUG\\(\\);/))))"}
 -doc_end
 
--doc_begin="Switch clauses not ending with the break statement are safe if an
-explicit comment indicating the fallthrough intention is present."
+-doc_begin="Switch clauses ending with an explicit comment indicating the fallthrough intention are safe."
 -config=MC3R1.R16.3,reports+={safe, "any_area(end_loc(any_exp(text(^(?s).*/\\* [fF]all ?through.? \\*/.*$,0..1))))"}
 -doc_end
 
diff --git a/automation/eclair_analysis/ECLAIR/tagging.ecl b/automation/eclair_analysis/ECLAIR/tagging.ecl
index b829655ca0..54772809ca 100644
--- a/automation/eclair_analysis/ECLAIR/tagging.ecl
+++ b/automation/eclair_analysis/ECLAIR/tagging.ecl
@@ -107,7 +107,7 @@ if(string_equal(target,"x86_64"),
 )
 
 if(string_equal(target,"arm64"),
-    service_selector({"additional_clean_guidelines","MC3R1.R16.6||MC3R1.R2.1||MC3R1.R5.3||MC3R1.R7.3"})
+    service_selector({"additional_clean_guidelines","MC3R1.R16.3||MC3R1.R16.6||MC3R1.R2.1||MC3R1.R5.3||MC3R1.R7.3"})
 )
 
 -reports+={clean:added,"service(clean_guidelines_common||additional_clean_guidelines)"}
diff --git a/docs/misra/deviations.rst b/docs/misra/deviations.rst
index 16fc345756..b11a5623c7 100644
--- a/docs/misra/deviations.rst
+++ b/docs/misra/deviations.rst
@@ -330,12 +330,34 @@ Deviations related to MISRA C:2012 Rules:
      - Tagged as `deliberate` for ECLAIR.
 
    * - R16.3
-     - Switch clauses ending with continue, goto, return statements are safe.
+     - Statements that change the control flow (i.e., break, continue, goto,
+       return) and calls to functions that do not return the control back are
+       \"allowed terminal statements\".
      - Tagged as `safe` for ECLAIR.
 
    * - R16.3
-     - Switch clauses ending with a call to a function that does not give
-       the control back (i.e., a function with attribute noreturn) are safe.
+     - An if-else statement having both branches ending with one of the allowed
+       terminal statemets is itself an allowed terminal statements.
+     - Tagged as `safe` for ECLAIR.
+
+   * - R16.3
+     - An if-else statement having an always true condition and the true
+       branch ending with an allowed terminal statement is itself an allowed
+       terminal statement.
+     - Tagged as `safe` for ECLAIR.
+
+   * - R16.3
+     - A switch clause ending with a statement expression which, in turn, ends
+       with an allowed terminal statement (e.g., the expansion of
+       generate_exception()) is safe.
+     - Tagged as `safe` for ECLAIR.
+
+   * - R16.3
+     - A switch clause ending with a do-while-false the body of which, in turn,
+       ends with an allowed terminal statement (e.g., PARSE_ERR_RET()) is safe.
+       An exception to that is the macro ASSERT_UNREACHABLE() which is
+       effective in debug build only: a switch clause ending with
+       ASSERT_UNREACHABLE() is not considered safe.
      - Tagged as `safe` for ECLAIR.
 
    * - R16.3
-- 
2.34.1
Re: [XEN PATCH v4] automation/eclair: extend existing deviations of MISRA C Rule 16.3
Posted by Jan Beulich 2 months, 2 weeks ago 
On 25.06.2024 08:46, Federico Serafini wrote:
> Update ECLAIR configuration to deviate more cases where an
> unintentional fallthrough cannot happen.
> 
> Tag Rule 16.3 as clean for arm.
> 
> Signed-off-by: Federico Serafini <federico.serafini@bugseng.com>
> Acked-by: Stefano Stabellini <sstabellini@kernel.org>

To add to my reply on the other series: As per above you even acked ...

> --- a/docs/misra/deviations.rst
> +++ b/docs/misra/deviations.rst
> @@ -330,12 +330,34 @@ Deviations related to MISRA C:2012 Rules:
>       - Tagged as `deliberate` for ECLAIR.
>  
>     * - R16.3
> -     - Switch clauses ending with continue, goto, return statements are safe.
> +     - Statements that change the control flow (i.e., break, continue, goto,
> +       return) and calls to functions that do not return the control back are
> +       \"allowed terminal statements\".
>       - Tagged as `safe` for ECLAIR.
>  
>     * - R16.3
> -     - Switch clauses ending with a call to a function that does not give
> -       the control back (i.e., a function with attribute noreturn) are safe.
> +     - An if-else statement having both branches ending with one of the allowed
> +       terminal statemets is itself an allowed terminal statements.
> +     - Tagged as `safe` for ECLAIR.
> +
> +   * - R16.3
> +     - An if-else statement having an always true condition and the true
> +       branch ending with an allowed terminal statement is itself an allowed
> +       terminal statement.
> +     - Tagged as `safe` for ECLAIR.
> +
> +   * - R16.3
> +     - A switch clause ending with a statement expression which, in turn, ends
> +       with an allowed terminal statement (e.g., the expansion of
> +       generate_exception()) is safe.
> +     - Tagged as `safe` for ECLAIR.
> +
> +   * - R16.3
> +     - A switch clause ending with a do-while-false the body of which, in turn,
> +       ends with an allowed terminal statement (e.g., PARSE_ERR_RET()) is safe.
> +       An exception to that is the macro ASSERT_UNREACHABLE() which is
> +       effective in debug build only: a switch clause ending with
> +       ASSERT_UNREACHABLE() is not considered safe.
>       - Tagged as `safe` for ECLAIR.

... this explicit statement regarding ASSERT_UNREACHABLE().

Jan
Re: [XEN PATCH v4] automation/eclair: extend existing deviations of MISRA C Rule 16.3
Posted by Stefano Stabellini 2 months, 2 weeks ago 
On Tue, 25 Jun 2024, Jan Beulich wrote:
> On 25.06.2024 08:46, Federico Serafini wrote:
> > Update ECLAIR configuration to deviate more cases where an
> > unintentional fallthrough cannot happen.
> > 
> > Tag Rule 16.3 as clean for arm.
> > 
> > Signed-off-by: Federico Serafini <federico.serafini@bugseng.com>
> > Acked-by: Stefano Stabellini <sstabellini@kernel.org>
> 
> To add to my reply on the other series: As per above you even acked ...
> 
> > --- a/docs/misra/deviations.rst
> > +++ b/docs/misra/deviations.rst
> > @@ -330,12 +330,34 @@ Deviations related to MISRA C:2012 Rules:
> >       - Tagged as `deliberate` for ECLAIR.
> >  
> >     * - R16.3
> > -     - Switch clauses ending with continue, goto, return statements are safe.
> > +     - Statements that change the control flow (i.e., break, continue, goto,
> > +       return) and calls to functions that do not return the control back are
> > +       \"allowed terminal statements\".
> >       - Tagged as `safe` for ECLAIR.
> >  
> >     * - R16.3
> > -     - Switch clauses ending with a call to a function that does not give
> > -       the control back (i.e., a function with attribute noreturn) are safe.
> > +     - An if-else statement having both branches ending with one of the allowed
> > +       terminal statemets is itself an allowed terminal statements.
> > +     - Tagged as `safe` for ECLAIR.
> > +
> > +   * - R16.3
> > +     - An if-else statement having an always true condition and the true
> > +       branch ending with an allowed terminal statement is itself an allowed
> > +       terminal statement.
> > +     - Tagged as `safe` for ECLAIR.
> > +
> > +   * - R16.3
> > +     - A switch clause ending with a statement expression which, in turn, ends
> > +       with an allowed terminal statement (e.g., the expansion of
> > +       generate_exception()) is safe.
> > +     - Tagged as `safe` for ECLAIR.
> > +
> > +   * - R16.3
> > +     - A switch clause ending with a do-while-false the body of which, in turn,
> > +       ends with an allowed terminal statement (e.g., PARSE_ERR_RET()) is safe.
> > +       An exception to that is the macro ASSERT_UNREACHABLE() which is
> > +       effective in debug build only: a switch clause ending with
> > +       ASSERT_UNREACHABLE() is not considered safe.
> >       - Tagged as `safe` for ECLAIR.
> 
> ... this explicit statement regarding ASSERT_UNREACHABLE().

You are right... I read the statement about ASSERT_UNREACHABLE() only in
the context of do-while-false. Let's continue the discussion in the
other email thread.

Patchew 2.1-devel-b67e4c2

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