https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93727
--- Comment #4 from jvdelisle at charter dot net --- An Update. I have the front end and runtime parsing for OUTPUT done and am now looking at the actual implementation. We have the printf series of functions available and can use the %A format specifier to create the hexidecimal float string. I want to note here that on input, apparently the F editing requires one to be able to READ a hexadecimal float with the F descriptor as well as the EX descriptor. See 13.7.2.3.2 part 7. Another aspect I am studying has to do with rounding. On output I assume we must support RU, RD, RN vs truncating. Considering that the purpose of this type of representation of a float is mostly for "looking under the hood" I initially was thinking simple truncation should suffice and if a user does not know they have not specified enough precision for all hexadecimals, tough beans. After all, in hexadecimal, it is always an exact fit. I am curious what others think about this. Regardless, we will need a new rounding function to round the hexadecimals before output. On input, obviously we need to do a new read function and for the F descriptor we will have to look ahead to identify that it is a hexadecimal before processing it, otherwise it just looks like a bad float.
