c++/5802: spurious "might be used uninitialized" warning with dynamic_cast

c++/5802: spurious "might be used uninitialized" warning with dynamic_cast

[poole]

>Number:         5802
>Category:       c++
>Synopsis:       spurious "might be used uninitialized" warning with dynamic_cast
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          rejects-legal
>Submitter-Id:   net
>Arrival-Date:   Fri Mar 01 07:46:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     poole@troilus.org
>Release:        gcc-3.0.4
>Organization:
>Environment:
Debian i686-linux-gnu unstable
>Description:
"g++ -W -O" (both 2.95.4-20011002 and 3.0.4 final) warns:
dyncast.cpp: In function `int test_func(group *)':
dyncast.cpp:22: warning: `class derived * dptr' might be used   uninitialized in this function

Intel's C++ compiler accepts the code, and I don't understand why g++ thinks it is used without initialization (or why using an int instead of string argument to get() makes the warning disappear), so I assume it's a g++ bug.
>How-To-Repeat:
compile with "g++ -W -O -c dyncast.cpp"
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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Re: c++/5802: spurious "might be used uninitialized" warning with dynamic_cast

[lerdsuwa]

Synopsis: spurious "might be used uninitialized" warning with dynamic_cast

State-Changed-From-To: open->analyzed
State-Changed-By: lerdsuwa
State-Changed-When: Wed Jun  5 08:45:34 2002
State-Changed-Why:
    Confirmed.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=5802