Removed error on naked, not fully complete, but I'll be doing more work on it during this Christmas, and some things do work.

Fixed taking delegate of final class method. see mini/delegate3.d.

gen/classes.cpp

@@ -1260,6 +1260,7 @@ LLValue* DtoVirtualFunctionPointer(DValue* inst, FuncDeclaration* fdecl)
 {
     // sanity checks
     assert(fdecl->isVirtual());
+    assert(!fdecl->isFinal());
     assert(fdecl->vtblIndex > 0); // 0 is always ClassInfo/Interface*
     assert(inst->getType()->toBasetype()->ty == Tclass);
 

gen/functions.cpp

@@ -628,13 +628,6 @@ void DtoDefineFunc(FuncDeclaration* fd)
     Logger::println("DtoDefineFunc(%s): %s", fd->toPrettyChars(), fd->loc.toChars());
     LOG_SCOPE;
 
-    // error on naked
-    if (fd->naked)
-    {
-        fd->error("naked is not supported");
-        fatal();
-    }
-
     // debug info
     if (global.params.symdebug) {
         Module* mo = fd->getModule();

gen/toir.cpp

@@ -1970,7 +1970,7 @@ DValue* DelegateExp::toElem(IRState* p)
     Logger::println("func: '%s'", func->toPrettyChars());
 
     LLValue* castfptr;
-    if (func->isVirtual())
+    if (func->isVirtual() && !func->isFinal())
         castfptr = DtoVirtualFunctionPointer(u, func);
     else if (func->isAbstract())
         assert(0 && "TODO delegate to abstract method");

tests/mini/delegate3.d

@@ -0,0 +1,18 @@
+module bar;
+
+class S
+{
+    int i;
+    final int foo()
+    {
+        return i;
+    }
+}
+
+void main()
+{
+    auto s = new S;
+    s.i = 42;
+    auto dg = &s.foo;
+    assert(dg() == 42);
+}