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 |  | 
The auxiliary table entries for the beginning of blocks and functions have the format shown in ``Format for beginning of block and function'':
Format for beginning of block and function
| Bytes | Declaration | Name | Description | 
|---|---|---|---|
| 0-3 | - | - | unused (filled with zeroes) | 
| 4-5 | unsigned short | x_lnno | C-source line number | 
| 6-11 | - | - | unused (filled with zeroes) | 
| 12-15 | long int | x_endndx | index of next entry past this block | 
| 16-17 | - | - | unused (filled with zeroes) |