[cocci] Searching for C++ delete expressions (with SmPL)?

[cocci] Searching for C++ delete expressions (with SmPL)?

[Markus Elfring]

Hello,

Another SmPL script example:
#spatch --c++
@display@
expression e;
@@
 delete
?[]
*e


Questionable test result (by the software combination “Coccinelle 1.3.0” for example):
Markus_Elfring@Sonne:…/Projekte/Coccinelle/janitor> /usr/bin/spatch --parse-cocci show_delete_expressions.cocci
…
warning: incompatible arity found on line 5
…
delete [] *e
…


How will clarification interests evolve further for this issue?

Regards,
Markus

Re: [cocci] Searching for C++ delete expressions (with SmPL)?

[Julia Lawall]

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On Fri, 8 Aug 2025, Markus Elfring wrote:

> Hello,
>
> Another SmPL script example:
> #spatch --c++
> @display@
> expression e;
> @@
>  delete
> ?[]
> *e
>
>
> Questionable test result (by the software combination “Coccinelle 1.3.0” for example):
> Markus_Elfring@Sonne:…/Projekte/Coccinelle/janitor> /usr/bin/spatch --parse-cocci show_delete_expressions.cocci
> …
> warning: incompatible arity found on line 5
> …
> delete [] *e
> …
>
>
> How will clarification interests evolve further for this issue?

In general, I don't think you can put ? on random subterms.  You could do
what you want with a disjunction.

julia

Re: [cocci] Searching for C++ delete expressions (with SmPL)?

[Markus Elfring]

>> Another SmPL script example:
>> #spatch --c++
>> @display@
>> expression e;
>> @@
>>  delete
>> ?[]
>> *e
>>
>>
>> Questionable test result (by the software combination “Coccinelle 1.3.0” for example):
>> Markus_Elfring@Sonne:…/Projekte/Coccinelle/janitor> /usr/bin/spatch --parse-cocci show_delete_expressions.cocci
>> …
>> warning: incompatible arity found on line 5
>> …
…> In general, I don't think you can put ? on random subterms.

How will the support evolve further for key word variants of the programming language “C++”?


>                                                              You could do
> what you want with a disjunction.

Under which circumstances will the mentioned “warning” be reconsidered better?

Regards,
Markus

Re: [cocci] Searching for C++ delete expressions (with SmPL)?

[Julia Lawall]

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On Fri, 8 Aug 2025, Markus Elfring wrote:

> >> Another SmPL script example:
> >> #spatch --c++
> >> @display@
> >> expression e;
> >> @@
> >>  delete
> >> ?[]
> >> *e
> >>
> >>
> >> Questionable test result (by the software combination “Coccinelle 1.3.0” for example):
> >> Markus_Elfring@Sonne:…/Projekte/Coccinelle/janitor> /usr/bin/spatch --parse-cocci show_delete_expressions.cocci
> >> …
> >> warning: incompatible arity found on line 5
> >> …
> …> In general, I don't think you can put ? on random subterms.
>
> How will the support evolve further for key word variants of the programming language “C++”?
>
>
> >                                                              You could do
> > what you want with a disjunction.
>
> Under which circumstances will the mentioned “warning” be reconsidered better?

None.

Re: [cocci] Searching for C++ delete expressions (with SmPL)?

[Markus Elfring]

>> Under which circumstances will the mentioned “warning” be reconsidered better?
> 
> None.

I hope that additional development resources will influence software evolution
in more desirable directions.

Regards,
Markus

Re: [cocci] Searching for C++ delete expressions (with SmPL)?

[Markus Elfring]

> In general, I don't think you can put ? on random subterms.  You could do
> what you want with a disjunction.

Will another SmPL script example trigger further collateral evolution?

#spatch --c++
@display@
expression e;
@@
(delete[]
*e
|delete
*e
)


Regards,
Markus

Re: [cocci] Searching for C++ delete expressions (with SmPL)?

[Markus Elfring]

> Will another SmPL script example trigger further collateral evolution?

Would you be looking for SmPL script variations which can handle known
C++ source code transformation patterns to some degree?

* https://clang.llvm.org/extra/clang-tidy/checks/readability/delete-null-pointer.html

* https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#r11-avoid-calling-new-and-delete-explicitly


Regards,
Markus