[Cfp-interest] WANT macros

[Jim Thomas]

At the Feb CFP meeting, Fred asked if the WANT macros that guard the library interfaces from the Parts of the CFP TS should  be specified in proposed changes to C11. Now they are specified in the TS Parts, but not in proposed changes to C11.

1. The only WANT macro defined in C11 now is for the interfaces specified in Annex K, which makes it easy to say what the guard covers. Our changes are not specified within an Annex (or Annexes). Also, our changes that are for Annex F are to be guard by different WANT macros, depending on what Part of the TS specified the interface. 

2. Our TS Parts might or might not go into the C standard. Note that there was no proposal to add the decimal FP TR to C11. If they go in, all or just pieces, some pieces might be in the main body of the standard or Annex F and not need a guard, and some might go in a new Annex so that a guard referring to EXTn of a (then) obsolete TS Part n might not be appropriate.

The guards seem appropriate for the specification while it's in the form of our TS, but maybe not, at least in the form the guards are in now, if the TS is integrated into the standard.

-Jim