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Tom St Deni #1 / 8

"long long" C99 question
Does "unsigned long long" mean a unsigned data type of at least 64 bits in C99? [simple question, answer yes or no, no lengthly flame wars please!] Thanks, Tom

Sat, 26 Jun 2004 09:57:16 GMT 


Simon Bibe #2 / 8

"long long" C99 question
Quote: > Does "unsigned long long" mean a unsigned data type > of at least 64 bits in C99?
Yes. Quote: > [simple question, answer yes or no, no lengthly > flame wars please!]
C99 5.2.4.2.1 Sizes of integer types: ... Their implementationdefined values shall be equal or greater in magnitude (absolute value) to those shown, with the same sign. ... maximum value for an object of type unsigned long long int ULLONG_MAX 18446744073709551615 // 2^64  1  Simon.

Sat, 26 Jun 2004 10:38:46 GMT 


Tom St Deni #3 / 8

"long long" C99 question
Quote:
> > Does "unsigned long long" mean a unsigned data type > > of at least 64 bits in C99? > Yes. > > [simple question, answer yes or no, no lengthly > > flame wars please!] > C99 5.2.4.2.1 Sizes of integer types: > ... > Their implementationdefined values shall be equal or greater in magnitude > (absolute value) to those shown, with the same sign. > ... > maximum value for an object of type unsigned long long int > ULLONG_MAX 18446744073709551615 // 2^64  1
Thank you. Tom

Sat, 26 Jun 2004 10:52:09 GMT 


Thomas Pfaf #4 / 8

"long long" C99 question
Quote:
> > > Does "unsigned long long" mean a unsigned data type > > > of at least 64 bits in C99? > > Yes. > > > [simple question, answer yes or no, no lengthly > > > flame wars please!] > > C99 5.2.4.2.1 Sizes of integer types: > > ... > > Their implementationdefined values shall be equal > > or greater in magnitude (absolute value) to those > > shown, with the same sign. > > ... > > maximum value for an object of type unsigned long > > long int > > ULLONG_MAX 18446744073709551615 // 2^64  1 > Thank you. > Tom
You can get a copy of the last (?) C99 draft here: http://anubis.dkuug.dk/JTC1/SC22/WG14/www/docs/n869/

Sat, 26 Jun 2004 12:17:38 GMT 


Bill Godfre #5 / 8

"long long" C99 question
Quote: > Does "unsigned long long" mean a unsigned data type of at least 64 bits in > C99?
At least 64 *value* bits, and zero or more padding bits. (A long long of 64 bits, ten of which are padding, would not be a conforming implementation.) Quote: > [simple question, answer yes or no, no lengthly flame wars please!]
Bill, Mu.

Sat, 26 Jun 2004 16:51:11 GMT 


Tom St Deni #6 / 8

"long long" C99 question
Quote: > You can get a copy of the last (?) C99 draft here: > http://anubis.dkuug.dk/JTC1/SC22/WG14/www/docs/n869/
Even cooler, thanks a bunch! Tom

Sat, 26 Jun 2004 19:41:16 GMT 


Tom St Deni #7 / 8

"long long" C99 question
Quote:
> > Does "unsigned long long" mean a unsigned data type of at least 64 bits in > > C99? > At least 64 *value* bits, and zero or more padding bits. > (A long long of 64 bits, ten of which are padding, would not be a > conforming implementation.)
That's what I meant though.... Typically when I mention a type "of nbits" I don't mean to say "nbits, nkbits of which are padding". Just like when I say a 192bit ECC key I don't mean 64bits of random values in the multiplicand and 128 fixed values of padding... Tom

Sat, 26 Jun 2004 19:42:27 GMT 


Lawrence Kir #8 / 8

"long long" C99 question
On Tuesday, in article
Quote:
>> > Does "unsigned long long" mean a unsigned data type of at least 64 bits >in >> > C99? >> At least 64 *value* bits, and zero or more padding bits. >> (A long long of 64 bits, ten of which are padding, would not be a >> conforming implementation.) >That's what I meant though.... Typically when I mention a type "of nbits" I >don't mean to say "nbits, nkbits of which are padding". >Just like when I say a 192bit ECC key I don't mean 64bits of random values >in the multiplicand and 128 fixed values of padding...
However padding is part of the definition of C types. It is not, AFAIK, part of the definition of ECC keys.  


Thu, 01 Jul 2004 22:17:48 GMT 

