bit-fields

[ak16]

Can bit-fields only be fields of a structure/union, never “normal”, “stand-alone” variables?

[Peter87]

Yes, that's right.

[ak16]

but why it is so...?

[ak16]

n with bit-fields we can only use char and int?

[Cubbi]

The type of a bit field can be any integral (that's bool, char, int, etc) or enum type. http://en.cppreference.com/w/cpp/language/bit_field

[ak16]

thanks cubbi for reply.

but in your reference link also bit field use with structure.

why we can not use it “stand-alone”?

[AbstractionAnon]

What would that accomplish?

A bit field that is not part of a struct would presumably occupy a full word so why not just use an integral type?

By forcing bit fields to be members of a struct, it becomes clear how the bits are packed.