> On Sep 5, 2017, at 1:01 PM, David Zarzycki via swift-dev > <swift-dev@swift.org> wrote: > > Hi Jordan, > > Thanks for thinking about this. For whatever it may be worth, I’m concerned > about 1) the ability to reorder declarations and 2) the “either/or” nature of > this proposal. > > First, reordering: The ability to reorder declarations is deeply ingrained > into the subconsciousness of Swift programmers and for good reasons.
There are a couple of other places where ordering of declarations matters in the ABI. The two most important ones I can think of right now are virtual methods and protocol methods. Both are called by performing an indexed lookup into a vtable. For methods, we were thinking that the ordering should first sort by availability annotation, and then by the mangled name of the method. This would allow re-ordering as well as adding new methods, as long as they had a ‘newer’ availability than anything that has come before. However, I like the idea of an @_abi (or similar) attribute as an escape hatch of some kind, in case we screw something up. Slava _______________________________________________ swift-dev mailing list swift-dev@swift.org https://lists.swift.org/mailman/listinfo/swift-dev
