12 Sep
2023
12 Sep
'23
4:43 p.m.
Note that there are transformations from double to float that still are UB. I couldn't find documentation on those.
Hrm, you're right. From the C99 draft spec § 6.3.1.5.2:
"When a double is demoted to float, [... i]f the value being converted can be represented exactly in the new type, it is unchanged. If the value being converted is in the range of values that can be represented but cannot be represented exactly, the result is either the nearest higher or nearest lower representable value, chosen in an implementation-defined manner. If the value being converted is outside the range of values that can be represented, the behavior is undefined."
That need not be in scope for this series, though.