Running
clang test.c -o test
On this file
#include <stdio.h>
#include <complex.h>
int main()
{
_Complex double z = 1.0 + _Imaginary_I * 2.0;
return 0;
}
fails to compile because of
error: use of undeclared identifier '_Imaginary_I'.
According to onlinepubs, _Imaginary_I is defined. What happened?