mark methods which really have no expressions and error on recursive abstract operator/array access calls (see #3376) (see #3636)

ast.ml

@@ -109,6 +109,7 @@ module Meta = struct
 		| NoCompletion
 		| NoDebug
 		| NoDoc
+		| NoExpr
 		| NoImportGlobal
 		| NoPackageRestrict
 		| NoStack

common.ml

@@ -423,6 +423,7 @@ module MetaInfo = struct
 		| NoCompletion -> ":noCompletion",("Prevents the compiler from suggesting completion on this field",[UsedOn TClassField])
 		| NoDebug -> ":noDebug",("Does not generate debug information into the Swf even if -debug is set",[UsedOnEither [TClass;TClassField];Platform Flash])
 		| NoDoc -> ":noDoc",("Prevents a type from being included in documentation generation",[])
+		| NoExpr -> ":noExpr",("Internally used to mark abstract fields which have no expression by design",[Internal])
 		| NoImportGlobal -> ":noImportGlobal",("Prevents a static field from being imported with import Class.*",[UsedOn TAnyField])
 		| NoPackageRestrict -> ":noPackageRestrict",("Allows a module to be accessed across all targets if found on its first type.",[Internal])
 		| NoStack -> ":noStack",("",[Platform Cpp])

typeload.ml

@@ -2007,6 +2007,7 @@ let init_class ctx c p context_init herits fields =
 								| None -> error (f.cff_name ^ ": Functions without expressions must have an explicit return type") f.cff_pos
 								| Some _ -> ()
 							end;
+							cf.cf_meta <- (Meta.NoExpr,[],cf.cf_pos) :: cf.cf_meta;
 							do_add := false;
 							do_bind := false;
 						end

typer.ml

@@ -940,6 +940,7 @@ let make_call ctx e params t p =
 
 let mk_array_get_call ctx (cf,tf,r,e1,e2o) c ebase p = match cf.cf_expr with
 	| None ->
+		if not (Meta.has Meta.NoExpr cf.cf_meta) then display_error ctx "Recursive array get method" p;
 		mk (TArray(ebase,e1)) r p
 	| Some _ ->
 		let et = type_module_type ctx (TClassDecl c) None p in
@@ -950,6 +951,7 @@ let mk_array_set_call ctx (cf,tf,r,e1,e2o) c ebase p =
 	let evalue = match e2o with None -> assert false | Some e -> e in
 	match cf.cf_expr with
 		| None ->
+			if not (Meta.has Meta.NoExpr cf.cf_meta) then display_error ctx "Recursive array get method" p;
 			let ea = mk (TArray(ebase,e1)) r p in
 			mk (TBinop(OpAssign,ea,evalue)) r p
 		| Some _ ->
@@ -2160,6 +2162,7 @@ and type_binop2 ctx op (e1 : texpr) (e2 : Ast.expr) is_assign_op wt p =
 		let map = apply_params a.a_params tl in
 		let make op_cf cf e1 e2 tret =
 			if cf.cf_expr = None then begin
+				if not (Meta.has Meta.NoExpr cf.cf_meta) then display_error ctx "Recursive operator method" p;
 				if not (Meta.has Meta.CoreType a.a_meta) then begin
 					(* for non core-types we require that the return type is compatible to the native result type *)
 					let e' = make {e1 with etype = Abstract.follow_with_abstracts e1.etype} {e1 with etype = Abstract.follow_with_abstracts e2.etype} in