Re: Preferred way to define 64-bit constants?

On 24 June 2012 18:23, Heikki Linnakangas
<heikki.linnakangas@enterprisedb.com> wrote:
> I just committed the patch to change XLogRecPtr into a 64-bit constant, and
> I did this in the patch:
>
> #define XLogSegmentsPerXLogId  (0x100000000LL / XLOG_SEG_SIZE)
>
> But I started to wonder, is that LL representation the preferred way to
> define 64-bit integer constants? I thought it is, but now that I grep
> around, I don't see any constants like that in the source tree.

This looks to be a long long int literal. That's only specified in the
C99 standard, as well as GNU C. It may very well not be a problem in
practice, but I'm told that some very esoteric compilers could baulk
at things like that.

http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html

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