runtime: use Stdlib starting on 4.07

src/runtime/ppx_deriving_runtime.cppo.ml

@@ -14,7 +14,13 @@ type nonrec int64 = int64
 type nonrec 'a lazy_t = 'a lazy_t
 type nonrec bytes = bytes
 
+#if OCAML_VERSION >= (4, 07, 0)
+module Stdlib = Stdlib
+
+include Stdlib
+#else
 module Pervasives = Pervasives
+
 module Char = Char
 module String = String
 module Printexc = Printexc
@@ -39,3 +45,4 @@ module Buffer = Buffer
 module Result = Result
 
 include Pervasives
+#endif

src/runtime/ppx_deriving_runtime.cppo.mli

@@ -22,6 +22,12 @@ type nonrec bytes = bytes
 (** {2 Predefined modules}
     {3 Operations on predefined types} *)
 
+#if OCAML_VERSION >= (4, 07, 0)
+module Stdlib : (module type of Stdlib)
+(* @since OCaml 4.07.0 *)
+
+include Stdlib
+#else
 module Pervasives : (module type of Pervasives with
   type fpclass = Pervasives.fpclass and
   type in_channel = Pervasives.in_channel and
@@ -31,6 +37,7 @@ module Pervasives : (module type of Pervasives with
   type ('a, 'b, 'c, 'd, 'e, 'f) format6 = ('a, 'b, 'c, 'd, 'e, 'f) Pervasives.format6 and
   type ('a, 'b, 'c, 'd) format4 = ('a, 'b, 'c, 'd) Pervasives.format4 and
   type ('a, 'b, 'c) format = ('a, 'b, 'c) Pervasives.format)
+
 include (module type of Pervasives with
   type fpclass = Pervasives.fpclass and
   type in_channel = Pervasives.in_channel and
@@ -83,3 +90,4 @@ module Format : (module type of Format with
   type formatter_out_functions = Format.formatter_out_functions and
   type formatter_tag_functions = Format.formatter_tag_functions and
   type formatter = Format.formatter)
+#endif