What is 'N/A (alignment)' in the *.map file? It is space that is lost due to alignment restrictions on segments.
The module summary will list 3 bytes as N/A (alignment) in this case.
Note that allocation in the reverse order (C,B,A) will generated 0 byte alignment "spill". The N/A (alignment) entry allows you to quickly see if there are any bytes wasted on alignment problems.
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