(C++) std::bad\_alloc

January 11, 2018 · View on GitHub

 

 

 

 

 

(C++) std::bad_alloc

 

std::bad_alloc is an exception and a derived class from std::exception. std::bad_alloc is thrown by new when new fails.

 

std::bad_alloc is defined in the header file new.

 

 

 

 

 

Example

 

 

#include <cassert> #include <limits> #include <boost/numeric/conversion/bounds.hpp> ///Example1 creates an array larger than memory can contain void Example1() {   //Assure that 2147483647 is the heighest value an int can contain using STL and Boost   assert(2147483647 == std::numeric_limits<int>::max());   assert(2147483647 == boost::numeric::bounds<int>::highest());   //Create the array with the largest possible size, the size its value   //being the heighest value an int can contain   const double * const i = new double[2147483647];   //Clean up   delete[] i; } #include <iostream> ///Examle2 leaks memory //(at my computer, the counter called i reached the value of 38) void Example2() {   for (int i=0; i!=100; ++i)   {     std::clog << i << '\n';     const double * const a = new double[10000000];     //delete[] a; //BAD: a must be deleted[], otherwise memory will leak   } } int main() {   //Choose your way to crash your computer:   Example1();   //Example2(); }

 

 

 

 

 

Screen output

 

terminate called after throwing an instance of 'std::bad_alloc'   what():  std::bad_alloc The program has unexpectedly finished.