[Bug c++/113687] New: -Warray-bounds is not emitted inside class method

[Bug c++/113687] New: -Warray-bounds is not emitted inside class method

[nmmm at nmmm dot nu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113687

            Bug ID: 113687
           Summary: -Warray-bounds is not emitted inside class method
           Product: gcc
           Version: 13.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nmmm at nmmm dot nu
  Target Milestone: ---

No warning -Warray-bounds is shown when code is inside class method, defined
inside the class body or outside if they are inline or constexpr.

struct S{
    int p(){
        int x[2] = {0, 0};

        return x[3]; // no warning shown
    }

    static int ps(){
        int x[2] = {0, 0};

        return x[3]; // no warning shown
    }

    int ps2inl();
    int ps2();
};

inline int S::ps2inl(){
    int x[2] = {0, 0};

    return x[3]; // no warning shown
}

int S::ps2(){
    int x[2] = {0, 0};

    return x[3]; // warning shown correctly
}

int f(){
    int x[2] = {0, 0};

    return x[3]; // warning shown correctly
}

int main(){
}

[Bug c++/113687] -Warray-bounds is not emitted inside class method

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113687

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |diagnostic

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The warning only happens if the vague linkage function is used. and IIRC that
is by design.

[Bug c++/113687] -Warray-bounds is not emitted inside class method

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113687

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Blocks|                            |56456
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2024-02-01

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #1)
> The warning only happens if the vague linkage function is used. and IIRC
> that is by design.

Yeah, we try to avoid diagnosing things on "dead" code and here the whole
functions are dead.  IIRC even -fanalyzer runs after cgraph removes unreachable
functions.

It would be still nice to diagnose these kind of trivial cases.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56456
[Bug 56456] [meta-bug] bogus/missing -Warray-bounds