temporaries

I've got a C++ data-structure that is a required "scratchpad" for other computations. It's not long-lived, and it's not frequently used so not performance critical. However, it includes a random number generator amongst other updatable tracking fields, and while the actual value of the generator isn't important, it is important that the value is updated rather than copied and reused. This means that in general, objects of this class are passed by reference. If an instance is only needed once, the most natural approach is to construct them whereever needed (perhaps using a factory method or a

Consider following code: class cFoo { private: int m1; char m2; public: int doSomething1(); int doSomething2(); int doSomething3(); } class cBar { private: cFoo mFoo; public: cFoo getFoo(){ return mFoo; } } void some_function_in_the_callstack_hierarchy(cBar aBar) { int test1 = aBar.getFoo().doSomething1(); int test2 = aBar.getFoo().doSomething2(); ... } In the line where getFoo() is called the compiler will generate a temporary object of cFoo, to be able to call doSomething1(). Does the compiler reuse the stack memory which is used for these temporary objects? How many stack memory will the

Section 12.2.5 in C++03 says " A temporary bound to a reference member in a constructor’s ctor-initializer (12.6.2) persists until the constructor exits " So I tried following program #include<iostream> using namespace std; struct foo { foo() { cout<<"foo c'tor"<<endl; } ~foo() { cout<<"foo d'tor"<<endl; } }; struct bar { const foo &ref; bar():ref(foo()) { cout<<"bar c'tor"<<endl; } }; int main() { bar obj; } The output I get is : foo c'tor foo d'tor bar c'tor Now according to standard, temporary generated by foo() in c'tor init-list of bar's c'tor will be destroyed after bar's c'tor so foo d