c++/5614: incorrect initialization of reference member in constructor initializer list

[dwoodward@sonicblue.com]

>Number:         5614
>Category:       c++
>Synopsis:       incorrect initialization of reference member in constructor initializer list
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Wed Feb 06 08:36:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Don Woodward, SONIC|blue Fellow
>Release:        gcc version 2.96 20000731 (Mandrake Linux 8.1 2.96-0.62mdk)
>Organization:
>Environment:
Mandrake Linux 8.1 on Pentium 450
>Description:
When initializing a reference member variable in a constructor initializer list, the reference gets initialized to garbage in this particular test case.  This is definitely an error; the same test program works correctly on previous versions of gcc and on MS VC++.

The test case, briefly is follows (consult attached file for actual test case):
class Foo
{
public:
    Foo() : m_ref( (1 == Func(&m_pInt) ? *m_pInt : *m_pInt) ) { }
private:
  int * m_pInt;
  int & m_ref;
  int Func(int ** ppInt) { *ppInt = new int; return 1; }
};

Accessing m_ref will cause a segmentation fault.
>How-To-Repeat:
1.  Compile the test program with: gcc test.cpp
2.  Run a.out
3.  Examine output, it should look like this:

      main()  pInt = 0x8051bb8
      main() &rInt = 0x8051bb8
Test::Test()  pInt = 0x8051bc8
Test::Test() &rInt = 0xbffff730

NOTE: the second &rInt in Test::Test() is bogus.  This is the problem.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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Content-Disposition: attachment; filename="test.cpp"

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