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I'm working with a program that makes use of std::vector a lot. Also there are lots of allocations/deallocations taking place, billions of them, and I'm trying to avoid as many of them as possible. Since I'm relatively new to C++, I have a few questions regarding allocations taking place when using a vector (e.g. when adding elements to it). I'm on a Win7 64-bit machine, the program is 32-bit and I'm using the current version of MinGW-compilers. I'd like to know, what happens in the following cases, i.e. if the vector is copied, passed as a reference, ... 1. std::vector<T> fillVector() { std::vector<T> returnVector; ... return returnVector; } std::vector<T> myVector = fillVector(); 2. std::vector<T>& fillVector() { std::vector<T>* returnVector = new std::vector<T>; ... return (*returnVector); } std::vector<T> myVector = fillVector(); 3. std::vector<T>* fillVector() { std::vector<T>* returnVector = new std::vector<T>; ... return returnVector; } std::vector<T>* myVector = fillVector(); And the following, different operations: 4. std::vector<T> myVector1; ... (myVector1 being filled) std::vector<T> myVector = myVector1; 5. std::vector<T>* myVector1 = new std::vector<T>; ... (myVector1 being filled) std::vector<T> myVector = (*myVector1); Assuming I don't want to change the argument in myFunction /changes in to myVector in myFunction wouldn't hurt the rest of the program: 6. void myFunction(std::vector<T> myParam) { ... } std::vector<T> myVector; ... (myVector being filled) myFunction(myVector); 7. void myFunction(st

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