From Jason Turner

[stmt.return]

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  ### The `return` statement <a id="stmt.return">[[stmt.return]]</a>
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  A function returns to its caller by the `return` statement.
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- A return statement with neither an *expression* nor a *braced-init-list*
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- can be used only in functions that do not return a value, that is, a
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- function with the return type cv `void`, a constructor (
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  [[class.ctor]]), or a destructor ([[class.dtor]]). A return statement
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- with an expression of non-void type can be used only in functions
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- returning a value; the value of the expression is returned to the caller
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- of the function. The value of the expression is implicitly converted to
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- the return type of the function in which it appears. A return statement
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- can involve the construction and copy or move of a temporary object (
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- [[class.temporary]]). A copy or move operation associated with a return
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- statement may be elided or considered as an rvalue for the purpose of
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- overload resolution in selecting a constructor ([[class.copy]]). A
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- return statement with a *braced-init-list* initializes the object or
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- reference to be returned from the function by copy-list-initialization (
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- [[dcl.init.list]]) from the specified initializer list.
 
 
 
 
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  ``` cpp
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  std::pair<std::string,int> f(const char* p, int x) {
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  return {p,x};
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  }
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  ```
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- Flowing off the end of a function is equivalent to a `return` with no
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- value; this results in undefined behavior in a value-returning function.
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- A return statement with an expression of type `void` can be used only in
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- functions with a return type of *cv* `void`; the expression is evaluated
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- just before the function returns to its caller.
 
 
 
 
 
 
 
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  ### The `return` statement <a id="stmt.return">[[stmt.return]]</a>
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  A function returns to its caller by the `return` statement.
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+ The *expr-or-braced-init-list* of a return statement is called its
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+ operand. A return statement with no operand shall be used only in a
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+ function whose return type is cv `void`, a constructor (
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  [[class.ctor]]), or a destructor ([[class.dtor]]). A return statement
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+ with an operand of type `void` shall be used only in a function whose
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+ return type is cv `void`. A return statement with any other operand
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+ shall be used only in a function whose return type is not cv `void`; the
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+ return statement initializes the glvalue result or prvalue result object
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+ of the (explicit or implicit) function call by copy-initialization (
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+ [[dcl.init]]) from the operand.
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+
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+ [*Note 1*: A return statement can involve an invocation of a
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+ constructor to perform a copy or move of the operand if it is not a
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+ prvalue or if its type differs from the return type of the function. A
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+ copy operation associated with a return statement may be elided or
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+ converted to a move operation if an automatic storage duration variable
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+ is returned ([[class.copy]]). — *end note*]
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+
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+ [*Example 1*:
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  ``` cpp
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  std::pair<std::string,int> f(const char* p, int x) {
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  return {p,x};
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  }
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  ```
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+ — *end example*]
 
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+ Flowing off the end of a constructor, a destructor, or a function with a
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+ cv `void` return type is equivalent to a `return` with no operand.
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+ Otherwise, flowing off the end of a function other than `main` (
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+ [[basic.start.main]]) results in undefined behavior.
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+
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+ The copy-initialization of the result of the call is sequenced before
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+ the destruction of temporaries at the end of the full-expression
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+ established by the operand of the return statement, which, in turn, is
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+ sequenced before the destruction of local variables ([[stmt.jump]]) of
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+ the block enclosing the return statement.
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