Are the static data members and static methods of a class in C++ static objects?

Question

From Programming Language Pragmatics, by Scott

Object lifetimes generally correspond to one of three principal storage allocation mechanisms, used to manage the object’s space:

1. Static objects are given an absolute address that is retained throughout the program’s execution.

2. Stack objects are allocated and deallocated in last-in, first-out order, usually in conjunction with subroutine calls and returns.

3. Heap objects may be allocated and deallocated at arbitrary times. They require a more general (and expensive) storage management algorithm.

Are the static data members and static methods of a class in C++ static objects in the PLP book?

Are the storage for the static data members and static methods of a class allocated at compile time or run time?

Where are they allocated?

Thanks.

Answer 1

Are the static data members and static methods of a class in C++ static objects in the PLP book?

Static data members, yes. And static objects inside functions, also yes. Also objects declared at file scope.

Are the storage for the static data members and static methods of a class allocated at compile time or run time?

If by allocation, you mean memory allocation, their memory footprint is reserved at compile time, and space is actually allocated in the process space by the linker at link time (or dynamic loader at load time). In either case, well before run time.

However, static objects declared at file or class scope are initialised at run time, before the main() function is called.

Static objects defined in functions are different. They are initialised the first time code flows over them.

Where are they allocated?

Wherever the linker or loader decides. This can be influenced by writing your own linker script (beyond the scope of this answer I'm afraid).