Fix CRC-64/XZ polynomial representation in PCF spec#6
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The constant 0x42F0E1EBA9EA3693 is the normal (non-reflected) polynomial of CRC-64/XZ, not the reflected one. Replace it with the actual reflected polynomial 0xC96C5795D7870F42 to match the convention already used for the two CRC-32 rows, and add a note mentioning the normal form for readers who need it (e.g. libraries that accept the normal poly). No on-disk format change; the check value 0x995DC9BBDF1939FA is unchanged. Fixes #2 https://claude.ai/code/session_01WvDqtNsESPu2XM4RuFWJ38
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Summary
Corrected the CRC-64/XZ polynomial representation in the PCF specification to use the reflected form as the primary value, with clarification about the normal (non-reflected) polynomial.
Changes
0x42F0E1EBA9EA3693to0xC96C5795D7870F420x42F0E1EBA9EA3693is the normal (non-reflected) polynomialDetails
The CRC-64/XZ specification now correctly documents the reflected polynomial (
0xC96C5795D7870F42) as the primary value used in the algorithm, since the parameters specifyrefin=trueandrefout=true. The normal polynomial form is now explicitly noted for reference, making the specification clearer for implementers.https://claude.ai/code/session_01WvDqtNsESPu2XM4RuFWJ38