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An Amazing recursion results in crash

A scenario, as per C++ specification supported and also supported by the GNU C++ compiler but not right to do so.

Example:

The following piece of code works both in the GNU C++ compiler as well as Microsoft C++ compiler. Code execution gives the right result (I mean expected output).

#include < vector >
#include < iostream >

class Simple
{
public:
Simple(unsigned int aInt) : memberInteger(aInt)
{

}

void Amaze()
{
myVector = { Simple(1), Simple(2) };
}

unsigned int memberInteger;
std::vector < Simple > myVector;
};

int main()
{
Simple s(0);
s.Amaze();
size_t sz = s.myVector.size();
return 0;
}


The size of my vector returns 2.

Now, I've changed the a code little bit and it gets compiled well in Gnu C++ compiler(4.9.2 and used "g++ -std=c++11 -Wall Simple_Defeat.cpp -o Simple_Defeat" to compile) but not in Microsoft C++ compiler (Checked with 2013):


#include < vector >
#include < iostream >

class Simple
{
    public:
  Simple (unsigned int aInt): memberInteger (aInt)
  {
             
  }

      unsigned int memberInteger;
      std::vector < Simple > myVector = { Simple(1), Simple(2) };
};

int main()
{
    Simple s(0);
    std::cout << s.myVector.size() << std::endl;
    return 0;
}


However, on execution, this one gives a core dump due to results in SIGSEGV. I think this is an edge case scenario in C++ (11) where specification allows initializing vector through initialization list but which results in code like below in Gnu C++:


Simple(unsigned int aInt) : memberInteger(aInt)
{
myVector = { Simple(1), Simple(2) };
}


As a result, it's an indefinite recursion causes a stack overflow. I came to this conclusion after examining the call stack which shows ~26,000 calls invocation to the ctor of Simple.

Happy programming!

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