c++/2320: incorrect order of destruction of function parameters

c++/2320: incorrect order of destruction of function parameters

[James.Kanze]

>Number:         2320
>Category:       c++
>Synopsis:       incorrect order of destruction of function parameters
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Mar 19 09:16:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     James Kanze
>Release:        gcc version 2.95.2 19991024
>Organization:
>Environment:
Windows 2000, CygWin 1.1.8
>Description:
According to ISO 14882:1998, paragraph 6.6/2: "On exit from scope
(however accomplished), destructors are called for all constructed
objects with automatic storage duration (named objects or temporaries)
that are declared in that scope, in the REVERSE order of their
declaration."  You will note that the objects 3 and 4, above, are
destructed in the order of their declaration, not the reverse order.
>How-To-Repeat:
Compile function with:
    g++ --verbose orderdtors.cc -o order
Then execute program with
    order
Output is
A::A(): 1
B::B(): 2
A::A(A): 3
B::B(B): 4
A::~A(): 3
B::~B(): 4
B::~B(): 2
A::~A(): 1

The fourth and fifth lines should be inverted.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: application/octet-stream; name="orderdtors.cc"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="orderdtors.cc"

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Re: c++/2320: incorrect order of destruction of function parameters

[Gabriel Dos Reis]

The following reply was made to PR c++/2320; it has been noted by GNATS.

From: Gabriel Dos Reis <gdr@codesourcery.com>
To: James.Kanze@dresdner-bank.com
Cc: gcc-gnats@gcc.gnu.org
Subject: Re: c++/2320: incorrect order of destruction of function parameters
Date: 19 Mar 2001 19:56:07 +0100

 James.Kanze@dresdner-bank.com writes:
 
 [...]
 
 | According to ISO 14882:1998, paragraph 6.6/2: "On exit from scope
 | (however accomplished), destructors are called for all constructed
 | objects with automatic storage duration (named objects or temporaries)
 | that are declared in that scope, in the REVERSE order of their
 | declaration."  You will note that the objects 3 and 4, above, are
 | destructed in the order of their declaration, not the reverse order.
 | >How-To-Repeat:
 | Compile function with:
 |     g++ --verbose orderdtors.cc -o order
 | Then execute program with
 |     order
 | Output is
 | A::A(): 1
 | B::B(): 2
 | A::A(A): 3
 | B::B(B): 4
 | A::~A(): 3
 | B::~B(): 4
 | B::~B(): 2
 | A::~A(): 1
 
 Hi,
 
 I can confirm the bug you're reporting in gcc-2.95.2.
 
 However "gcc version 3.0 20010314 (prerelease)" gives the correct
 behavior
 
 A::A(): 1
 B::B(): 2
 A::A(A): 3
 B::B(B): 4
 B::~B(): 4
 A::~A(): 3
 B::~B(): 2
 A::~A(): 1
 
 
 -- Gaby
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