Re: c++/5605: Wrong constructor is called when anonymous object is created in catch block.

Re: c++/5605: Wrong constructor is called when anonymous object is created in catch block.

[nathan]

Synopsis: Wrong constructor is called when anonymous object is created in catch block.

State-Changed-From-To: open->analyzed
State-Changed-By: nathan
State-Changed-When: Sun Sep 15 11:58:05 2002
State-Changed-Why:
    confirmed. Weird.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=5605

Re: c++/5605: Wrong constructor is called when anonymous object is created in catch block.

[Wolfgang Bangerth]

The following reply was made to PR c++/5605; it has been noted by GNATS.

From: Wolfgang Bangerth <bangerth@ticam.utexas.edu>
To: gcc-bugs@gcc.gnu.org, <gcc-gnats@gcc.gnu.org>
Cc:  
Subject: Re: c++/5605: Wrong constructor is called when anonymous object is
 created in catch block.
Date: Wed, 22 Jan 2003 14:53:17 -0600 (CST)

 This is actually a parser problem:
 --------------------
 struct A {
     A();
     A(int) {};
 };
 
 main() {
   try { throw 666; } 
   catch (int & e) {
     A (e);   //***
   }
 }
 -------------------------------
 gcc parses the marked line as a declaration of variable e, and tries to 
 call the default constructor for A, which yields a linker error since 
 undefined. The submitter claims that this should rather create an unnamed 
 variable of type A, and run the constructor A::A(int) on it; since 
 defined, this would link properly.
 
 icc7, by the way, says:
 x.cc(9): error: "e" has already been declared in the current scope
       A (e);
          ^
 so applies the "this is a named variable" ethic too and spews an 
 additional error. 
 
 I don't know what is right or wrong here.
 
 W.
 
 -------------------------------------------------------------------------
 Wolfgang Bangerth             email:            bangerth@ticam.utexas.edu
                               www: http://www.ticam.utexas.edu/~bangerth/
 
 

c++/5605: Wrong constructor is called when anonymous object is created in catch block.

[cs]

>Number:         5605
>Category:       c++
>Synopsis:       Wrong constructor is called when anonymous object is created in catch block.
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Wed Feb 06 00:26:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     cs@plesk.com
>Release:        at least 2.95.3 and 3.0.3
>Organization:
>Environment:
I'm sure it doesn't matter, at least on FreeBSD 4.3, 4.5 and RedHat 7.2 on i386.
>Description:
When executing a code like:

try {
   // .....
} catch (SomeException &e) {
     SomeClass(e);
}
will be called SomeClass::SomeClass() constructor instead of
SomeClass(SomeException) or something like.
>How-To-Repeat:
Just compile and run file attached. it outputs 
A::A()
instead of 
A::A(int)
>Fix:
Don't know
>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: application/octet-stream; name="test.cpp"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="test.cpp"

I2luY2x1ZGUgPHN0ZGlvLmg+CmNsYXNzIEEgewpwdWJsaWM6CglBKCkKCXsKCQlwcmludGYoIiVz
XG4iLCBfX1BSRVRUWV9GVU5DVElPTl9fKTsKCX0KCUEoaW50KQoJewoJCXByaW50ZigiJXNcbiIs
IF9fUFJFVFRZX0ZVTkNUSU9OX18pOwoJfQp9OwoKbWFpbigpCnsKCXRyeSB7CgkJdGhyb3cgNjY2
OwoJfSBjYXRjaCAoaW50ICYgZSkgewoJCUEgKGUpOwoJfQp9Cg==