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* c++/8171: pointers to member functions comparison
@ 2002-10-08 11:06 Jozef Kosoru
0 siblings, 0 replies; 2+ messages in thread
From: Jozef Kosoru @ 2002-10-08 11:06 UTC (permalink / raw)
To: gcc-gnats
>Number: 8171
>Category: c++
>Synopsis: pointers to member functions comparison
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: unassigned
>State: open
>Class: rejects-legal
>Submitter-Id: net
>Arrival-Date: Tue Oct 08 11:06:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator: Jozef Kosoru <zyzstar@ibl.sk>
>Release: 3.1.1
>Organization:
>Environment:
Mandrake Linux
>Description:
g++ is not able to compile the following code:
----------------------------------------------------
#include <iostream>
using namespace std;
struct A
{
int f() {}
};
struct B : A
{
};
int main()
{
int (A::*pa)() = &A::f;
int (B::*pb)() = &B::f;
cout << boolalpha << (pa == pb) << endl;
}
----------------------------------------------------
...but according to ISO (see 5.10/2) this code should compile and result of the pointer comparsion would be 'true'.
>How-To-Repeat:
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: c++/8171: pointers to member functions comparison
@ 2002-11-04 8:15 bangerth
0 siblings, 0 replies; 2+ messages in thread
From: bangerth @ 2002-11-04 8:15 UTC (permalink / raw)
To: gcc-bugs, gcc-prs, nobody, zyzstar
Synopsis: pointers to member functions comparison
State-Changed-From-To: open->analyzed
State-Changed-By: bangerth
State-Changed-When: Mon Nov 4 08:15:06 2002
State-Changed-Why:
I agree. In particular, the referenced part of the standard
states:
Pointer to member conversions(_conv.mem_) and
qualification conversions (_conv.qual_) are performed
to bring them to a common type.
This does not seem to happen. (Conversion by hand yields
the desired result though, so there is a way to work
around this problem.)
W.
PS: As a sidenote (for the curious), the standard also says
this on comparing pointers to member functions:
if either [operand] is a pointer to a virtual member func-
tion, the result is unspecified
That seems like a trap you don't want to fall into... (And
there isn't even a way for the compiler to warn you about.)
http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8171
^ permalink raw reply [flat|nested] 2+ messages in thread
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2002-10-08 11:06 c++/8171: pointers to member functions comparison Jozef Kosoru
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