cdefs.h File Reference

Definitions for builtin attributes and compiler directives. More...

#include <sys/cdefs.h>

Go to the source code of this file.

Macros
#define	__noreturn   __attribute__((__noreturn__))
	Identify a function that will never return.
#define	__pure   __attribute__((__const__))
	Identify a function that has no side effects other than its return, and only uses its arguments for any work.
#define	__unused   __attribute__((__unused__))
	Identify a function or variable that may be unused.
#define	__used   __attribute__((used))
	Prevent a symbol from being removed from the binary.
#define	__weak   __attribute__((weak))
	Identify a function or variable that may be overridden by another symbol.
#define	__dead2   __noreturn /* BSD compat */
	Alias for __noreturn.
#define	__pure2   __pure /* ditto */
	Alias for __pure.
#define	__likely(exp)   __builtin_expect(!!(exp), 1)
	Directive to inform the compiler the condition is in the likely path.
#define	__unlikely(exp)   __builtin_expect(!!(exp), 0)
	Directive to inform the compiler the condition is in the unlikely path.
#define	__deprecated   __attribute__((deprecated))
	Mark something as deprecated.
#define	__depr(m)   __attribute__((deprecated(m)))
	Mark something as deprecated, with an informative message.
#define	__printflike(fmtarg, firstvararg)    __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
	Identify a function as accepting formatting like printf().
#define	__scanflike(fmtarg, firstvararg)    __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
	Identify a function as accepting formatting like scanf().
#define	__fallthrough   /* Fall through */
#define	__always_inline   inline __attribute__((__always_inline__))
	Ask the compiler to always inline a given function.
#define	__no_inline   __attribute__((__noinline__))
	Ask the compiler to never inline a given function.
#define	__RESTRICT
#define	__extension__
#define	inline   __inline__

Detailed Description

Definitions for builtin attributes and compiler directives.

This file contains definitions of various attribute directives in shorter forms for use in programs. These typically aid in optimizations or provide the compiler with extra information about a symbol.

Author

Megan Potter

Lawrence Sebald

Falco Girgis