Bug 13830 – Circular dependency between interface and implementation segfault the compiler

I tried to use the CRTP in D to generate an interface at compile time based on another interface and the implementation. Unfortunately, it segfaulted the compiler. ```` import std.stdio, std.traits; template RESTServer(I, Impl) { private abstract class IRESTServer/* : I*/ { //final override void test() { assert(0); } void test(Context ctx); } int abuseTheCompiler() { foreach (method; __traits(allMembers, Impl)) { foreach (overload; MemberFunctionsTuple!(Impl, method)) { pragma(msg, __traits(identifier, overload)); } } return 42; } static assert(abuseTheCompiler()); alias RESTServer = IRESTServer; } struct Context { string ip; } interface MyAPI { void test(); } class MyAPIImpl : RESTServer!(MyAPI, MyAPIImpl) { override: void test(Context ctx) { writeln(ctx.ip); } } void main() { auto c = new MyAPIImpl(); c.test(Context("10.24.50.42")); } ```` Question: should such code be valid ? It allows an interesting pattern for code generators.

Does changing `Impl` to alias parameter instead of type parameter change anything? Anyway, compiler shouldn't crash. Please paste here exact ICE error line too.

The segfault is a dup of issue 13668, and fortunately it's already fixed in git-head. *** This issue has been marked as a duplicate of issue 13668 ***