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Copyright 2016 Joyent, Inc.

ASSERT.H 3HEAD "Jan 14, 2015"
assert.h, assert - verify program assertion

#include <assert.h>

The <assert.h> header defines the assert() macro. It refers to the macro NDEBUG which is not defined in the header. If NDEBUG is defined as a macro name before the inclusion of this header, the assert() macro is defined simply as:

#define assert(ignore)((void) 0)

Otherwise, the macro behaves as described in assert(3C).

The assert() macro is redefined according to the current state of NDEBUG each time <assert.h> is included.

The assert() macro is implemented as a macro, not as a function. If the macro definition is suppressed in order to access an actual function, the behavior is undefined.

The <assert.h> header also defines the static_assert() macro. This macros is similar to assert(); however, while assert() is used at program execution time, static_assert() is evaluated and checked by the compiler at compilation-time.


See attributes(5) for descriptions of the following attributes:

Interface Stability Standard

assert(3C), attributes(5), standards(5)