powerof2 - test if a value is a power of 2

       The arguments may be evaluated more than once.

       Because this macro is implemented using bitwise operations, some negative  values  can  invoke  undefined
       behavior.   For example, the following invokes undefined behavior: powerof2(INT_MIN);.  Call it only with
       unsigned types to be safe.

       This macro returns true if x is a power of 2, and false otherwise.

       0  is  considered  a  power of 2.  This can make sense considering wrapping of unsigned integers, and has
       interesting properties.

       Standard C library (libc)

       powerof2 - test if a value is a power of 2

       True or false, if x is a power of 2 or not, respectively.

stdc_bit_ceil(3), stdc_bit_floor(3)

Linux man-pages 6.9.1                              2024-05-02                                        powerof2(3)

       BSD.

#include<sys/param.h>intpowerof2(x);