c/23

The next generation of the C standard.

See:.

Removed

 * Old-style function declarations and definitions
 * Representations for signed integers other than two's complement
 * Permission that /-prefixed character constants and string literals may be not UTF-16/32
 * Mixed wide string literal concatenation
 * Support for calling with zero size (the behavior becomes undefined)
 * and
 * is not provided as a macro defined in (becomes a keyword)
 * is not provided as a macro defined in (becomes a keyword)

Deprecated

 * Old feature-test macros
 * function specifier
 * attribute token
 * asctime
 * ctime
 * (use the appropriate type-specific macro (, etc) instead)
 * Definition of following numeric limit macros in (they should be used via )
 * ctime
 * (use the appropriate type-specific macro (, etc) instead)
 * Definition of following numeric limit macros in (they should be used via )

New language features

 * Decimal floating-point types (,, and )
 * Bit-precise integers
 * Binary integer constants
 * character constants
 * Type change of string literals
 * Digit separator
 * Empty initializer
 * Attributes
 * Unnamed parameters in function definitions
 * Identical cvr-qualifications for array types and their element types
 * Single-argument
 * becomes a keyword (may be a predefined macro for compatibility reasons)
 * becomes a keyword (may be a predefined macro for compatibility reasons)
 * Labels followed by declarations and {{ttb|} }}
 * constant and the associated type
 * and become keywords (may be predefined macros for compatibility reasons)
 * New preprocessor directives
 * Pragmas for rounding direction
 * becomes a keyword (may be a predefined macro for compatibility reasons)
 * becomes a keyword (may be a predefined macro for compatibility reasons)
 * Labels followed by declarations and {{ttb|} }}
 * constant and the associated type
 * and become keywords (may be predefined macros for compatibility reasons)
 * New preprocessor directives
 * Pragmas for rounding direction
 * Pragmas for rounding direction
 * Pragmas for rounding direction
 * Pragmas for rounding direction
 * Pragmas for rounding direction

Feature test macros for optional features

 * Indicates IEEE-754 binary floating-point arithmetic and required math functions are supported.
 * This macro supersedes.
 * Indicates IEEE-754 decimal floating-point arithmetic and required math functions are supported.
 * Indicates IEEE-754 complex arithmetic and required math functions are supported.
 * This macro supersedes.
 * Indicates IEEE-754 complex arithmetic and required math functions are supported.
 * This macro supersedes.
 * This macro supersedes.

Library features

 * Extended binary floating-point math functions
 * Decimal floating-point math functions
 * - variants for existing and new floating-point math functions
 * Floating-point formatting functions
 * Library support for UTF-8
 * type alias
 * type alias
 * test macro
 * POSIX functions
 * Extensions for and
 * Extensions for and  function families
 * and length modifiers for  and  respectively
 * ,, and length modifiers for , , and  respectively
 * conversion specifier for unsigned integer types
 * Macro constants for width of integer types
 * Additional numeric limit macros for floating-point types
 * Library version-test macros
 * type alias
 * test macro
 * POSIX functions
 * Extensions for and
 * Extensions for and  function families
 * and length modifiers for  and  respectively
 * ,, and length modifiers for , , and  respectively
 * conversion specifier for unsigned integer types
 * Macro constants for width of integer types
 * Additional numeric limit macros for floating-point types
 * Library version-test macros
 * and length modifiers for  and  respectively
 * ,, and length modifiers for , , and  respectively
 * conversion specifier for unsigned integer types
 * Macro constants for width of integer types
 * Additional numeric limit macros for floating-point types
 * Library version-test macros
 * Library version-test macros