18 Language support library [language.support]

18.10 Other runtime support [support.runtime]

18.10.3 Header <cstdbool> synopsis [cstdbool.syn]

#define __bool_true_false_are_defined 1
1

The contents of the header <cstdbool> are the same as the C standard library header <stdbool.h>, with the following changes: The header <cstdbool> and the header <stdbool.h> shall not define macros named bool, true, or false.

See also: ISO C 7.18.