8 Statements [stmt.stmt]

8.2 Label [stmt.label]

A label can be added to a statement or used anywhere in a compound-statement.
The optional attribute-specifier-seq appertains to the label.
The only use of a label with an identifier is as the target of a goto.
No two labels in a function shall have the same identifier.
A label can be used in a goto statement before its introduction.
Case labels and default labels shall occur only in switch statements.