[Bug c++/12341] Request for additional warning for variable shadowing

[Bug c++/12341] Request for additional warning for variable shadowing

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12341

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Blocks|                            |87403
   Last reconfirmed|2005-12-11 23:28:15         |2020-5-18
                 CC|                            |msebor at gcc dot gnu.org

--- Comment #3 from Martin Sebor <msebor at gcc dot gnu.org> ---
Reconfirming with GCC 11.0.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87403
[Bug 87403] [Meta-bug] Issues that suggest a new warning

[Bug c++/12341] Request for additional warning for variable shadowing

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12341

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |joseph.h.garvin at gmail dot com

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 45615 has been marked as a duplicate of this bug. ***

[Bug c++/12341] Request for additional warning for variable shadowing

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12341

--- Comment #5 from Eric Gallager <egallager at gcc dot gnu.org> ---
is this expected to be a new argument accepted by the `-Wshadow=` flag, or its
own separate flag entirely?

[Bug c++/12341] Request for additional warning for variable shadowing

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12341

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This inheritance case is "name hiding" and we have other requests for warnings
about it. I think it should be distinct from -Wshadow.

[Bug c++/12341] Request for additional warning for variable shadowing

[priour.be at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=12341

Benjamin Priour <priour.be at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |priour.be at gmail dot com

--- Comment #7 from Benjamin Priour <priour.be at gmail dot com> ---
Hi,

I'm currently fixing this, I've put it under -Wshadow for now, as it is still
about shadowing names, but I could add a -Wname-hiding or something akin to it.

What about the visibility of the base class field ?

I think that in snippet (1) below, a warning should be issued, as we can
imagine Base being virtual with private field x and a friend function
foo(Base*) taking polymorphic argument Base*, then Derived inherits of Base,
with public field x.
There might be an ambiguity upon accessing x in a call to foo((Base *)
derived).

Therefore, I believe the warning should be issued no matter the visibility of
the fields within the parent's class.

However, if Grandpa class is privately inherited by Base class, then I'd expect
Derived to not issue warnings for its fields named only after Grandpa's.


// Snippet (1)
class Base {
private:
  int x;
};
class Derived : public Base {
public:
 int x; // issue warning despite Base::x private
};

// Snippet (2)
class Grandpa;
class Base : private Grandpa;
class Derived : public Base; // No warnings emitted for eponymous fields of
Grandpa's

[Bug c++/12341] Request for additional warning for variable shadowing

[hayim at dv-networks dot com]

------- Comment #2 from hayim at dv-networks dot com  2005-12-13 09:17 -------
I agree.
I hope this warning will be added in near future versions of g++.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12341

[Bug c++/12341] New: Request for additional warning for variable shadowing

[bero at arklinux dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12341

           Summary: Request for additional warning for variable shadowing
           Product: gcc
           Version: 3.3.2
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bero at arklinux dot org
                CC: gcc-bugs at gcc dot gnu dot org

class A { 
public: 
        A() { } 
protected: 
        int aaa; 
}; 
 
class B:public A { 
public: 
        B():A() { } 
protected: 
        int aaa; 
}; 
 
compiles without a warning, and is a potential source of hard to trace problems 
(while it can, of course, be used intentionally). 
 
It may be useful to give a warning akin to the one given in the case of 
 
void blah(int a) 
{ 
	int a; 
}

[Bug c++/12341] Request for additional warning for variable shadowing

[bangerth at dealii dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12341


bangerth at dealii dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2003-09-19 17:57:14
               date|                            |


------- Additional Comments From bangerth at dealii dot org  2003-09-19 17:57 -------
Right. Makes sense. 
W.