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c++/1193: g++ 3.2 creates multiple constructors: gdb 5.3 can't set breakpoints


>Number:         1193
>Category:       c++
>Synopsis:       g++ 3.2 creates multiple constructors: gdb 5.3 can't set breakpoints
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Apr 27 12:18:00 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     joachim dot eibl at gmx dot de
>Release:        gdb 5.3 in combination with  g++ 3.2
>Organization:
>Environment:
Suse 8.2, i586
>Description:
Now this is not new, but I want to point out that these two bugs are related.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=3187
http://sources.redhat.com/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gdb&pr=267

In the little program below I want to place a breakpoint in the constructor via gdb. But it will never be called. The reason is that the binary contains the constructor function twice. The breakpoint will be set in the first function. But the second function is called.

// File simpletest.cpp: g++ -g3 simpletest.cpp
class A
{
public:
   A();
private:
   bool bFlag;
   int  num;
};

int main(int argc, char *argv[])
{
  A* pA = new A;
  return 0;
}

A::A()
{
   bFlag = false;   // Here I want to place a breakpoint
   num = 9;
}

It is visible even in the assembler output, created via 
g++ -S simpletest.cpp
Both constructors are identical and follow behind each other.
...
.globl _ZN1AC2Ev
        .type   _ZN1AC2Ev, @function
_ZN1AC2Ev:
.LFB6:
        pushl   %ebp
.LCFI4:
        movl    %esp, %ebp
.LCFI5:
        movl    8(%ebp), %eax
        movb    $0, (%eax)
        movl    8(%ebp), %eax
        movl    $9, 4(%eax)
        popl    %ebp
        ret
.LFE6:
        .size   _ZN1AC2Ev, .-_ZN1AC2Ev
        .align 2
.globl _ZN1AC1Ev
        .type   _ZN1AC1Ev, @function
_ZN1AC1Ev:
.LFB8:
        pushl   %ebp
.LCFI6:
        movl    %esp, %ebp
.LCFI7:
        movl    8(%ebp), %eax
        movb    $0, (%eax)
        movl    8(%ebp), %eax
        movl    $9, 4(%eax)
        popl    %ebp
        ret
...

(I'll also post this message on the gcc-bugs-site.)
>How-To-Repeat:

>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:


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