On 20 December 2016 at 12:24, Mike via Digitalmars-d-announce <firstname.lastname@example.org> wrote: > On Monday, 19 December 2016 at 19:53:06 UTC, Iain Buclaw wrote: > >> The compiler doesn't actually generate any code that peeks inside >> TypeInfo. It only generates the reference to the right typeinfo to pass to >> library runtime functions - or on request via typeid(). It doesn't >> actually care about the data stored inside. And that's the angle I've taken >> when laying out the actual data - if you provide the fields we want to >> populate, then we'll populate them. If you omit a few, then the compiler >> won't bother with them. Because at the end of the day, it's druntime >> library that uses and makes sense of the TypeInfo data provided. The >> compile just says: "Well, this is as much as I'm willing to tell you about >> the type." > > > Ok, that's interesting, but what if you don't want TypeInfo at all? Can you > omit the TypeInfo structure entirely from object.d? Or perhaps you still > need to declare it in object.d, but since the compiler doesn't find any > fields to populate, it results in an empty struct? I'd really hate to have > to add empty TypeInfo_XXX classes to my object.d though. >
Yeah, there are two logical steps that need ratifying. 1) -fno-rtti should be a flag that is honoured by the compiler. 2) Runtime functions that "lower" to a C function call should not generate RTTI if all information about the type is known at compile-time. There are ideas floating around to improve , but for the time being however, marking all functions as @nogc catches almost all cases where this happens.