The identifiers shown in Table 5 are reserved for use as keywords (that is, they are unconditionally treated as keywords in phase 7) except in an attribute-token:
| alignas | continue | friend | register | true |
| alignof | decltype | goto | reinterpret_cast | try |
| asm | default | if | return | typedef |
| auto | delete | inline | short | typeid |
| bool | do | int | signed | typename |
| break | double | long | sizeof | union |
| case | dynamic_cast | mutable | static | unsigned |
| catch | else | namespace | static_assert | using |
| char | enum | new | static_cast | virtual |
| char16_t | explicit | noexcept | struct | void |
| char32_t | export | nullptr | switch | volatile |
| class | extern | operator | template | wchar_t |
| const | false | private | this | while |
| constexpr | float | protected | thread_local | |
| const_cast | for | public | throw |
[ Note: The export and register keywords are unused but are reserved for future use. — end note ]
Furthermore, the alternative representations shown in Table 6 for certain operators and punctuators ([lex.digraph]) are reserved and shall not be used otherwise:
| and | and_eq | bitand | bitor | compl | not |
| not_eq | or | or_eq | xor | xor_eq |