#include <assert.h>

void assert(scalar expression);


Partially implemented


IEEE Std 1003.1-2017


The purpose is to insert program diagnostics. The assert() macro shall insert diagnostics into programs, it shall expand to a void expression. When it is executed, if expression (which shall have a scalar type) is false (that is, compares equal to 0), assert() shall write information about the particular call that failed on stderr and shall call abort().

The information written about the call that failed shall include the text of the argument, the name of the source file, the source file line number, and the name of the enclosing function, the latter are, respectively, the values of the preprocessing macros __FILE__ and __LINE__ and of the identifier __func__.

Forcing a definition of the name NDEBUG, either from the compiler command line or with the preprocessor control statement #define NDEBUG ahead of the #include <assert.h> statement, shall stop assertions from being compiled into the program.

Return value#

The assert() macro shall not return a value.


No errors are defined.



Known bugs#


See Also#

  1. Standard library functions

  2. Table of Contents