assert.h File Reference

Contains several macros usable for making assertions. More...

This graph shows which files directly or indirectly include this file:

Macros
#define	STRINGIFY(S)   #S
	Converts a macro parameter into a string.
#define	assert_size(TYPE, SIZE)    static_assert(sizeof(TYPE) == (SIZE), "Wrong size for " STRINGIFY(TYPE))
	Statically ensure (at compile time) that a data type (or variable) has the expected size.
#define	assert(EXP)
	Ensure (at execution time) an expression evaluates to true, print an error message and stop the CPU otherwise.

Functions
void	assertion_failed (const char *exp, const char *func, const char *file, int line)
	Handles a failed assertion.

Detailed Description

Contains several macros usable for making assertions.

Depending on the type of assertion (either static or at runtime), a failing assertion will trigger an error. For static assertion, this error will be shown at compile time and abort compilation. Runtime assertions will trigger a message containing details about the error occurred and will make the CPU die.

Macro Definition Documentation

assert

#define assert

(

EXP

)

Value:

    do { \
        if (__builtin_expect(!(EXP), 0)) { \
            assertion_failed(STRINGIFY(EXP), __func__, __FILE__, __LINE__); \
        } \
    } while (false)

Ensure (at execution time) an expression evaluates to true, print an error message and stop the CPU otherwise.

Parameters

EXP	The expression to be checked

assert_size

#define assert_size	(		TYPE,
			SIZE
	)		static_assert(sizeof(TYPE) == (SIZE), "Wrong size for " STRINGIFY(TYPE))

Statically ensure (at compile time) that a data type (or variable) has the expected size.

Parameters

TYPE	The type to be checked
SIZE	Expected size in bytes

STRINGIFY

#define STRINGIFY

(

S

)

#S

Converts a macro parameter into a string.

Parameters

S	Expression to be converted

Returns

stringified version of S

Function Documentation

assertion_failed()

void assertion_failed	(	const char *	exp,
		const char *	func,
		const char *	file,
		int	line
	)

Handles a failed assertion.

This function will print a message containing further information about the failed assertion and stops the current CPU permanently.

Note

This function should never be called directly, but only via the macro assert.

Parameters

exp	Expression that did not hold
func	Name of the function in which the assertion failed
file	Name of the file in which the assertion failed
line	Line in which the assertion failed