On Thu, 25 Apr 2013, Marek Polacek wrote:
This is an attempt to fix PR57066, where when folding logb call,
we returned -Inf for logb(-Inf), which is not correct.
I had to adjust one testcase, because it checked for a wrong value.
What I don't know yet is what we should return for -Nan, it should be
in C9X standard, but I don't have it by hand.
Doesn't matter:
"Recommended practice
If a function with one or more NaN arguments returns a NaN result, the
result should be the same as one of the NaN arguments (after possible type
conversion), except perhaps for the sign."
"F.9.3.11 The logb functions
— logb(±0) returns −∞ and raises the ‘‘divide-by-zero’’ floating-point
exception.
— logb(±∞) returns ∞."
--
Marc Glisse
