[PATCH] adjust sprintf range for AIX QNaN output (PR 86571)

[Martin Sebor]

On 08/02/2018 01:46 PM, Martin Sebor wrote:
> The recently added test gcc.dg/torture/builtin-sprintf.c
> to verify that the sprintf result computed by GCC matches
> libc's for Infinity and NaN has been failing on AIX which
> formats NaN as either QNaN or SNaN, contrary to C/POSIX
> requirements.  The attached tweak adjusts the result
> computed by GCC to include the AIX format.  If there are
> no objections I'll commit the tweak later this week and
> backport it to GCC 8 the next.

I have committed this change as r263312.

In the longer term, I think it might be best to introduce an OS
target hook to describe sprintf implementation-defined details
like the format of infinite values (i.e., inf or infinity, nan
or qnan/snan), and perhaps also %p format and anything else that
might be relevant.

I'll wait a bit before backporting it GCC 8 and 7 in case there
are any comments/concerns.

Martin