Does it make sense to pass STL container by reference to function parameters to save memory and increase speed?

Question

Programming

Or do modern compilers (primarily gcc) optimize this moment themselves?
The question arose after reading this article www.habrahabr.ru/post/117193, paragraph: Transferring everything and everywhere by pointers (links)

Answer 1

Certainly has. How should the compiler know, maybe you really want to work with a copy, and not with the original.
Another matter, return from function. RVO (return value optimization) works there, so you can not worry, but simply give the container.

Answer 2

Or do modern compilers (primarily gcc) optimize this moment themselves?

The compiler has no right to do this, because it will not be an optimization, but a sabotage.

Answer 3

It doesn't "make sense", but the first rule. But the compiler is forbidden to optimize this, the semantics of the code changes from this, and not only optimization is done.

Answer 4

const container_type &container - if the function does not change the state of the container.
container_type &container - if it changes.
Read The C++ Programming Language by Stanley Lippman.