//fork/throw SEGFAULT issue

//a SEGFAULT occurs under these circumstances:
// 1. compile with g++-4 (4.3.4 20090804) on cygwin 1.7.5-1
//      - g++-3 does not have this issue
//      - occurrences in cyg 1.7.4-1 were not reproducible (other causes?)
// 2. fork at least once
// 3. throw a derived exception class in the child
// 4. where the derived class contains a std::string member
// 5. catch std::exception
//To see the SEGFAULT, you will need error_start=dumper.exe 
//or something similar in the CYGWIN environmental variable



#include <string>
#include <exception>

#include <cstdlib>

#include <sys/types.h>
#include <unistd.h>

using namespace std;



class stringexcept : public exception {

public:

  stringexcept() : exception(), _what() {}

  virtual ~stringexcept() throw() {}

  string _what;

};



int main(int, char**) {

  try {

    pid_t pid = fork();
      
    if (pid == 0) {

      //child - throw and SEGFAULT
      throw stringexcept();
        
    } else if (pid > 0) {

      //parent
      exit(0);
        
    } else {
        
      //fork() failed
      exit(1);
        
    } //if parent/child
  } catch(exception e) {

    //do nothing

  }
    
  return 0;
}