| Message ID | 679b1948690fecf06c9e81b398f7bf9bf5a292d2.1719407840.git.nicola.vetrini@bugseng.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | address several violations of MISRA Rule 20.7 | expand |
On Wed, 26 Jun 2024, Nicola Vetrini wrote: > MISRA C Rule 20.7 states: "Expressions resulting from the expansion > of macro parameters shall be enclosed in parentheses". > > The helper macro bitmap_switch has parameters that cannot be parenthesized > in order to comply with the rule, as that would break its functionality. > Moreover, the risk of misuse due developer confusion is deemed not > substantial enough to warrant a more involved refactor, thus the macro > is deviated for this rule. > > No functional change. > > Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
diff --git a/docs/misra/safe.json b/docs/misra/safe.json index c213e0a0be3b..3f18ef401c7d 100644 --- a/docs/misra/safe.json +++ b/docs/misra/safe.json @@ -60,6 +60,14 @@ }, { "id": "SAF-7-safe", + "analyser": { + "eclair": "MC3R1.R20.7" + }, + "name": "MC3R1.R20.7: deliberately non-parenthesized macro argument", + "text": "A macro parameter expands to an expression that is non-parenthesized, as doing so would break the functionality." + }, + { + "id": "SAF-8-safe", "analyser": {}, "name": "Sentinel", "text": "Next ID to be used" diff --git a/xen/include/xen/bitmap.h b/xen/include/xen/bitmap.h index b9f980e91930..6ee39aa35ac6 100644 --- a/xen/include/xen/bitmap.h +++ b/xen/include/xen/bitmap.h @@ -103,10 +103,13 @@ extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order); #define bitmap_switch(nbits, zero, small, large) \ unsigned int n__ = (nbits); \ if (__builtin_constant_p(nbits) && !n__) { \ + /* SAF-7-safe Rule 20.7 non-parenthesized macro argument */ \ zero; \ } else if (__builtin_constant_p(nbits) && n__ <= BITS_PER_LONG) { \ + /* SAF-7-safe Rule 20.7 non-parenthesized macro argument */ \ small; \ } else { \ + /* SAF-7-safe Rule 20.7 non-parenthesized macro argument */ \ large; \ }
MISRA C Rule 20.7 states: "Expressions resulting from the expansion of macro parameters shall be enclosed in parentheses". The helper macro bitmap_switch has parameters that cannot be parenthesized in order to comply with the rule, as that would break its functionality. Moreover, the risk of misuse due developer confusion is deemed not substantial enough to warrant a more involved refactor, thus the macro is deviated for this rule. No functional change. Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com> --- Changes in v2: - Switched to a comment-based deviation to allow other tools to pick this deviation up automatically. --- docs/misra/safe.json | 8 ++++++++ xen/include/xen/bitmap.h | 3 +++ 2 files changed, 11 insertions(+)