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599. [dec.tr] Say "octets" instead of "bytes."

Section: 3.1 [dec.tr::trdec.types.encodings] Status: TRDec Submitter: Daniel Krugler Opened: 2006-05-28 Last modified: 2016-01-31

Priority: Not Prioritized

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Discussion:

Daniel writes in a private email:

- 3.1 'Decimal type encodings' says in its note:

"this implies that 
sizeof(std::decimal::decimal32) == 4, 
sizeof(std::decimal::decimal64) == 8, and 
sizeof(std::decimal::decimal128) == 16."

This is a wrong assertion, because the definition of 'byte' in 1.7 'The C+ + memory model' of ISO 14882 (2nd edition) does not specify that a byte must be necessarily 8 bits large, which would be necessary to compare with the specified bit sizes of the types decimal32, decimal64, and decimal128.

Proposed resolution:

Change 3.1 as follows:

The three decimal encoding formats defined in IEEE-754R correspond to the three decimal floating types as follows:

• decimal32 is a decimal32 number, which is encoded in four consecutive bytes octets (32 bits)
• decimal64 is a decimal64 number, which is encoded in eight consecutive bytes octets (64 bits)
• decimal128 is a decimal128 number, which is encoded in 16 consecutive bytes octets (128 bits)

[Note: this implies that sizeof(std::decimal::decimal32) == 4, sizeof(std::decimal::decimal64) == 8, and sizeof(std::decimal::decimal128) == 16. --end note]