ST12: Unexpected destructor called

Question

Hi
I have SunStudio12 on some Solaris 10 machine.
CC -VCC: Sun C++ 5.9 SunOS_sparc 2007/05/03
uname -aSunOS sungolem 5.10 Generic_125100-09 sun4u sparc SUNW,Sun-Fire-V250
I have some problems with the following test program which terminates with core due to unexpected call of destructor:
file:test.cc
#include <iostream>
using namespace std;
class A
    char *_a;
  public:
    A(const char *t) { cout <<"A:ctor["<<t<<"]"<<endl; setdata(t);}
    virtual ~A() { cout <<"A:dtor["<<_a<<"]"<<endl; delete _a;_a = NULL;}
    void setdata(const char *data) {  _a = new char [strlen(data)+1];strcpy(_a,data);}
    const char * getdata() const { return _a;}
    A( const A &a){ cout <<"A:copy_ctor["<<a._a<<"]"<<endl;setdata(a._a);}
bool operator == (const A&l, const A&r)
{  return (strcmp(l.getdata(),r.getdata()) == 0?true:false);}
int main()
    A c ("321");
    cout <<"1"<<endl;
    //cout << "compare"<<(c == A("123")?"true":"false")<<endl;
    cout <<"2"<<endl;
    bool f = false;
    bool isA = false;
    if(
     (f!= false)
     (c == (isA?A("123"):A("321"))))
     cout <<"3"<<endl;
    else
     cout <<"4"<<endl;
    cout <<"5"<<endl;
}Compilation:
CC -g -o test.x test.ccResult of execution:
test.xA:ctor[321]
1
2
A:dtor[Segmentation fault (core dumped)
I tried with dbx:
>
1
2
A:dtor[signal SEGV (no mapping at the fault address) in strlen at 0xff030e38
0xff030e38: strlen+0x0018:      ldub     [%o2], %o1
Current function is A::~A
11 virtual ~A() { cout <<"A:dtor["<<_a<<"]"<<endl; delete _a;_a = NULL;}
(dbx) where
[1] strlen(0x3, 0x21fd0, 0x3, 0xff37f4e8, 0x3, 0xff3798f0), at 0xff030e38
[2] std::operator<<(0x21fd0, 0x3, 0xff37c194, 0x1, 0x0, 0x148), at 0xff3041e8
=>[3] A::~A(this = 0xffbfcfcc), line 11 in "test.cc"
[4] main(), line 33 in "test.cc"
(dbx) print *this
*this = {
_a = 0x3 "<bad address 0x3>"
Interesting thing - if you set optimization level to -xO3 then program works as expected:
CC -xO3 -g -o test.x test.cc
test.xA:ctor[321]
1
2
4
5
A:dtor[321]
Then I uncomment commented line and compiled without -g option:
CC -o test.x test.ccIn such case program exits unexpectedly without core:
test.x A:ctor[321]
1
compareA:ctor[123]
false
A:dtor[123]
2
A:dtor[
If option -g is added, then program works as expected:
CC -g -o test.x test.cc
test.xA:ctor[321]
1
compareA:ctor[123]
false
A:dtor[123]
2
4
5
A:dtor[321]
What is wrong?
PS: I tried all above with latest SunStudio11 and problem is not reproduced.
Thanks

Answer 1

It is likely a compiler bug. Thanks for reporting the problem. I filed bug 6570096.
Dmitry