The packed type attribute specifies that
a type must have the smallest possible alignment.
Note
This type attribute is a GNU compiler extension that the ARM compiler supports.
ErrorsTaking the address of a field with the packed attribute
or in a structure with the packed attribute yields
a __packed-qualified pointer. The compiler will
produce a type error if you attempt to implicitly cast this pointer
to a non-__packed pointer. This contrasts with
its behavior for address-taken fields of a #pragma packed
structure.
The compiler generates a warning message if you use this attribute
in a typedef.
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