Support v12 CMT files in analysis

compiler/ext/config.ml

@@ -4,6 +4,17 @@ and ast_impl_magic_number = "Caml1999M022"
 
 and ast_intf_magic_number = "Caml1999N022"
 
-and cmt_magic_number = "Caml1999T022"
+(* Current magic written to .cmt/.cmti files. Bump this whenever the marshalled
+   typedtree/CMT shape changes. *)
+and cmt_magic_number = "Caml1999T023"
+
+(* Older CMT magics that are safe for current readers to consume. This lets
+   editor analysis support previous compiler versions while still writing a new
+   magic for artifacts generated by this compiler. Only add values whose
+   marshalled typedtree shape is compatible with the current one. *)
+let supported_cmt_magic_numbers = [cmt_magic_number; "Caml1999T022"]
+
+let is_supported_cmt_magic_number magic_number =
+  List.exists (String.equal magic_number) supported_cmt_magic_numbers
 
 let load_path = ref ([] : string list)

compiler/ext/config.mli

@@ -26,6 +26,10 @@ val ast_intf_magic_number : string
 (* Magic number for file holding an interface syntax tree *)
 val ast_impl_magic_number : string
 
-(* Magic number for file holding an implementation syntax tree *)
 val cmt_magic_number : string
-(* Magic number for compiled interface files *)
+(* Magic number written to current compiled typedtree files *)
+
+val supported_cmt_magic_numbers : string list
+(* Current and compatible older compiled typedtree magic numbers *)
+
+val is_supported_cmt_magic_number : string -> bool

compiler/ml/cmt_format.cppo.ml

@@ -119,13 +119,13 @@ let read filename =
   try
     let magic_number = read_magic_number ic in
     let cmi, cmt =
-      if magic_number = Config.cmt_magic_number then
+      if Config.is_supported_cmt_magic_number magic_number then
         None, Some (input_cmt ic)
       else if magic_number = Config.cmi_magic_number then
         let cmi = Cmi_format.input_cmi ic in
         let cmt = try
                     let magic_number = read_magic_number ic in
-                    if magic_number = Config.cmt_magic_number then
+                    if Config.is_supported_cmt_magic_number magic_number then
                       let cmt = input_cmt ic in
                       Some cmt
                     else None

compiler/ml/parsetree.ml

@@ -290,10 +290,6 @@ and expression_desc =
     (* for i = E1 to E2 do E3 done      (flag = Upto)
        for i = E1 downto E2 do E3 done  (flag = Downto)
     *)
-  | Pexp_for_of of pattern * expression * expression
-    (* for pattern of array_expr do body_expr *)
-  | Pexp_for_await_of of pattern * expression * expression
-    (* for await pattern of iterable_expr do body_expr *)
   | Pexp_constraint of expression * core_type (* (E : T) *)
   | Pexp_coerce of expression * unit * core_type
     (* (E :> T)        (None, T)
@@ -322,6 +318,10 @@ and expression_desc =
   (* . *)
   | Pexp_await of expression
   | Pexp_jsx_element of jsx_element
+  | Pexp_for_of of pattern * expression * expression
+    (* for pattern of array_expr do body_expr *)
+  | Pexp_for_await_of of pattern * expression * expression
+(* for await pattern of iterable_expr do body_expr *)
 
 (* an element of a record pattern or expression *)
 and 'a record_element = {lid: Longident.t loc; x: 'a; opt: bool (* optional *)}

compiler/ml/typedtree.ml

@@ -119,14 +119,14 @@ and expression_desc =
       * expression
       * direction_flag
       * expression
-  | Texp_for_of of Ident.t * Parsetree.pattern * expression * expression
-  | Texp_for_await_of of Ident.t * Parsetree.pattern * expression * expression
   | Texp_send of expression * meth * expression option
   | Texp_letmodule of Ident.t * string loc * module_expr * expression
   | Texp_letexception of extension_constructor * expression
   | Texp_assert of expression
   | Texp_pack of module_expr
   | Texp_extension_constructor of Longident.t loc * Path.t
+  | Texp_for_of of Ident.t * Parsetree.pattern * expression * expression
+  | Texp_for_await_of of Ident.t * Parsetree.pattern * expression * expression
 
 and meth = Tmeth_name of string
 

compiler/ml/typedtree.mli

@@ -220,14 +220,14 @@ and expression_desc =
       * expression
       * direction_flag
       * expression
-  | Texp_for_of of Ident.t * Parsetree.pattern * expression * expression
-  | Texp_for_await_of of Ident.t * Parsetree.pattern * expression * expression
   | Texp_send of expression * meth * expression option
   | Texp_letmodule of Ident.t * string loc * module_expr * expression
   | Texp_letexception of extension_constructor * expression
   | Texp_assert of expression
   | Texp_pack of module_expr
   | Texp_extension_constructor of Longident.t loc * Path.t
+  | Texp_for_of of Ident.t * Parsetree.pattern * expression * expression
+  | Texp_for_await_of of Ident.t * Parsetree.pattern * expression * expression
 
 and meth = Tmeth_name of string