[C][C++] Print size of type at compile time

sizeof_compile_time.c

char (*__kaboom)[sizeof( xxx )] = 1;

// xxx can be a variable or a data type
// See https://stackoverflow.com/questions/20979565/how-can-i-print-the-result-of-sizeof-at-compile-time-in-c

// Exemple of code:
//    char (*__kaboom)[sizeof( long long )] = 1;
// GCC error:
//    error: invalid conversion from 'int' to 'char (*)[8]' [-fpermissive]
// So sizeof(long long) == 8

Works great. Surprised the C standard people haven't added a way to do this.