A
return statement with
no operand shall be used only in a function whose return type is
cv void, a
constructor, or a
destructor.A
return statement with an operand of type
void shall be used only
in a function whose return type is
cv void.A
return statement with any other operand shall be used only
in a function whose return type is not
cv void;
the
return statement initializes the
glvalue result or prvalue result object of the (explicit or implicit) function call
by
copy-initialization from the operand
.[
Note 1:
A
return statement can involve
an invocation of a constructor to perform a copy or move of the operand
if it is not a prvalue or if its type differs from the return type of the function
.A copy operation associated with a
return statement can be elided or
converted to a move operation if an automatic storage duration variable is returned (
[class.copy.elision])
. —
end note]
[
Example 1:
std::pair<std::string,int> f(const char* p, int x) {
return {p,x};
}
—
end example]
[
Example 2:
class A {
~A() {}
};
A f() { return A(); }
—
end example]
Flowing off the end of
a constructor,
a destructor, or
a non-coroutine function with a
cv void return type is
equivalent to a
return with no operand
.