Re: Using 128-bit integers for sum, avg and statistics aggregates

On 2015-03-18 14:00:51 -0700, Peter Geoghegan wrote:
> Anyway, I think that it's not quite the same. For one thing, we're
> talking about a GCC extension, not a type described by C99. We don't
> care about snprintf support, for example.

I don't see that that has any consequence wrt Andreas' test.

> For another, Andreas has chosen to lump together __int128 and unsigned
> __int128 into one test, where the latter really doesn't receive
> coverage.

On my urging actually. It's pretty darn unlikely that only one variant
will work. Useless configure tests just cost time. We're testing a gcc
extension here, as you point out, it'll not just stop working for
unsigned vs signed.

The reason we need a link test (vs just a compile test) is that gcc
links to helper functions to do math - even if they're not present on
the target platform. Compiling will succeed, but linking won't.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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