Type support

Basic types

Fundamental types defined by the language

Additional basic types and convenience macros

Defined in header <stddef.h>
size_t	unsigned integer type returned by the sizeof operator (typedef)
ptrdiff_t	signed integer type returned when subtracting two pointers (typedef)
NULL	implementation-defined null pointer constant (macro constant)
max_align_t (C11)	a type with alignment requirement as great as any other scalar type (typedef)
offsetof	byte offset from the beginning of a struct type to specified member (function macro)
Defined in header <stdalign.h>
alignas (C11)	convenience macro, expands to keyword _Alignas (keyword macro)
alignof (C11)	convenience macro, expands to keyword _Alignof (keyword macro)
__alignas_is_defined (C11)	expands to integer constant 1 (macro constant)
__alignof_is_defined (C11)	expands to integer constant 1 (macro constant)
Defined in header <stdnoreturn.h>
noreturn (C11)	convenience macro, expands to _Noreturn (keyword macro)

Boolean type support (since C99)

Fixed width integer types (since C99)

Numeric limits

References

• C11 standard (ISO/IEC 9899:2011):
• 7.15 Alignment <stdalign.h> (p: 268)
• 7.19 Common definitions <stddef.h> (p: 288)
• 7.23 _Noreturn <stdnoreturn.h> (p: 361)
• C99 standard (ISO/IEC 9899:1999):
• 7.19 Common definitions <stddef.h> (p: 254)
• C89/C90 standard (ISO/IEC 9899:1990):
• 4.1.5 Common definitions <stddef.h>

See also