910623 - why bit fields cannot have indirection?

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in the following struct:

C#

struct
{
    bool simultaneousAction:1;
    bool action[7]:1;
};

i wonder why C2033 must be generated?! logically it must not be erroneous. there must be a byte first of which (LSb) be called simultaneousAction, the next bit be called action[0] and the last one (MSb) be called action[6].
what's the problem with this scenario and why do i get the following error?

error C2033: 'AsServoMotorProperties::<unnamed-tag>::action' : bit field cannot have indirection

Posted 13-Sep-12 2:51am

ilostmyid2

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pasztorpisti 13-Sep-12 8:55am

A C++ array can not be packed. Period.

Richard MacCutchan 13-Sep-12 9:20am

Because you cannot directly address single bits, an array of bits is not a valid construct.

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Jochen Arndt · Answer 1 · 2012-09-13T03:03:00

Solution 1

The underlying type of a bit field must be an integral type. An array is similar to a pointer and therefore not an integral type.

Posted 13-Sep-12 3:03am

Jochen Arndt