On 11/25/2019 2:56 PM, Markus Armbruster wrote:
Tao Xu <tao3...@intel.com> writes:
Support full 64bit precision, modify related test cases.
That's not true in general: long double need not be any wider than
double.
It might be true on the host machines we support, but I don't know. If
we decide to rely on it, we better make the build fail when the host
machine doesn't meet our expectations, preferably in configure.
[...]
- if ((val * mul >= 0xfffffffffffffc00) || val < 0) {
+ /* Values > UINT64_MAX overflow uint64_t */
+ if ((val * mul > UINT64_MAX) || val < 0) {
retval = -ERANGE;
goto out;
}
Not portable. If it was, we'd have made this changd long ago :)
OK. So the suitable solution is what you suggested in v14?
"A possible alternative is to parse the numeric part both as a double
and as a 64 bit unsigned integer, then use whatever consumes more
characters. This enables providing full 64 bits unless you actually use
a fraction."
I will try this way.
