8 Statements [stmt.stmt]

8.4 Compound statement or block [stmt.block]

A compound statement (also known as a block) groups a sequence of statements into a single statement.
A label at the end of a compound-statement is treated as if it were followed by a null statement.
[Note 1:
A compound statement defines a block scope ([basic.scope]).
A declaration is a statement ([stmt.dcl]).
— end note]