Christoph Berg <christoph(dot)berg(at)credativ(dot)de> writes:
> Re: Tom Lane 2017-02-20 <30737(dot)1487598355(at)sss(dot)pgh(dot)pa(dot)us>
>> Hmph. We haven't touched that code in awhile, and certainly not in the
>> 9.4.x branch. I'd have to agree that this must be a toolchain change.
> FYI, in the meantime we could indeed trace it back to an libc issue on
> Jessie:
I wonder whether it's a compiler change, maybe along the lines of
rearranging the computation so that it gives a slightly different result.
Although you'd think that 10.0/10.0 would give exactly 1.0 no matter what.
Still, it'd be worth comparing the assembly code for your test program.
regards, tom lane