These were on the agenda for today's cancelled call.

2. Is parent/child alignment rule too strict?
 Spec property description for alignment says "The alignment of a child component must be less than
 or equal the alignment of its parent element, sequence or choice". Experiments with creating DFDL schema
 from C structures have shown that this rule is violated. It seems unnecessary.  Specifically, C ensures that the alignment
 of objects in a repeating structure is preserved by rounding up the length of the structure, rather than aligning it.

 3. Does DFDL need to support signed integer types with lengthUnits 'bits'?
 Spec only allows unsigned integers to have lengthUnits 'bits', but it is possible in C structures to delare
 bit fields for signed integers. They behave like two's complement. It looks like the spec is being
 too restrictive in its types for 'bits'.

Regards

Steve Hanson
Architect, Data Format Description Language (DFDL)
Co-Chair, OGF DFDL Working Group
IBM SWG, Hursley, UK
smh@uk.ibm.com
tel:+44-1962-815848
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