24.3.15 The Allocation Order of Bit-Field
The memory ordering of bit-fields into their storage unit is not specified by the C Language Standard. In the CCI, the first bit defined is the least significant bit (LSb) of the storage unit in which it is allocated.
Example
The following shows a structure containing bit-fields being
defined.
struct {
unsigned lo : 1;
unsigned mid :6;
unsigned hi : 1;
} foo;
The bit-field lo
is assigned the least significant bit of
the storage unit assigned to the structure foo
. The bit-field
mid
is assigned the next 6 least significant bits, and
hi
, the most significant bit of that same storage unit byte.
Differences
This is identical with the previous operation of all compilers.
Migration to the CCI
No action required.