According to this answer, Qt just replaces const references with copies. EDIT: Apparently not always the case… I just did a basic test program with one thread, and the reference was passed correctly. Its const-ness remained intact, as well. Anyways, yes, you do need to be wary of the variable going out of scope, plus … Read more
However, in main, I pass the same variable, referenced both by a and by b. As f modifies b, it also modifies a, which it supposedly shouldn’t When f modifies what b refers to, it does not modify a. It modifies what a refers to, but that is okay since b is not const. It’s … Read more
For your final question: how can a const reference keep pointing to an R-Value (anonymous variable) Here is the answer. The C++ language says that a local const reference prolongs the lifetime of temporary values until the end of the containing scope, but saving you the cost of a copy-construction (i.e. if you were to use an … Read more