diff --git a/VERSION b/VERSION
index 3fbafe2df..738426160 100644
--- a/VERSION
+++ b/VERSION
@@ -1,4 +1,4 @@
-3.12.0+dev25 (2010-05-20)
+3.12.0+dev26 (2010-06-04)
 
 # The version string is the first line of this file.
 # It must be in the format described in stdlib/sys.mli
diff --git a/boot/ocamlc b/boot/ocamlc
index 38b6bb9a7..e2a7ed90b 100755
Binary files a/boot/ocamlc and b/boot/ocamlc differ
diff --git a/boot/ocamldep b/boot/ocamldep
index 14034fbf2..ec792d394 100755
Binary files a/boot/ocamldep and b/boot/ocamldep differ
diff --git a/boot/ocamllex b/boot/ocamllex
index d60895f3e..7cc08b38f 100755
Binary files a/boot/ocamllex and b/boot/ocamllex differ
diff --git a/parsing/parser.mly b/parsing/parser.mly
index 87a565961..4f9bcc58b 100644
--- a/parsing/parser.mly
+++ b/parsing/parser.mly
@@ -93,14 +93,19 @@ let mkuminus name arg =
       mkexp(Pexp_constant(Const_int64(Int64.neg n)))
   | "-", Pexp_constant(Const_nativeint n) ->
       mkexp(Pexp_constant(Const_nativeint(Nativeint.neg n)))
-  | _, Pexp_constant(Const_float f) ->
+  | ("-" | "-."), Pexp_constant(Const_float f) ->
       mkexp(Pexp_constant(Const_float(neg_float_string f)))
   | _ ->
       mkexp(Pexp_apply(mkoperator ("~" ^ name) 1, ["", arg]))
 
 let mkuplus name arg =
-  match name, arg.pexp_desc with
-  | "+", desc -> mkexp desc
+  let desc = arg.pexp_desc in
+  match name, desc with
+  | "+", Pexp_constant(Const_int _)
+  | "+", Pexp_constant(Const_int32 _)
+  | "+", Pexp_constant(Const_int64 _)
+  | "+", Pexp_constant(Const_nativeint _)
+  | ("+" | "+."), Pexp_constant(Const_float _) -> mkexp desc
   | _ ->
       mkexp(Pexp_apply(mkoperator ("~" ^ name) 1, ["", arg]))
 
diff --git a/stdlib/pervasives.ml b/stdlib/pervasives.ml
index c4f0bcfd8..22dfa8fc2 100644
--- a/stdlib/pervasives.ml
+++ b/stdlib/pervasives.ml
@@ -51,6 +51,7 @@ external (||) : bool -> bool -> bool = "%sequor"
 (* Integer operations *)
 
 external (~-) : int -> int = "%negint"
+external (~+) : int -> int = "%identity"
 external succ : int -> int = "%succint"
 external pred : int -> int = "%predint"
 external (+) : int -> int -> int = "%addint"
@@ -77,6 +78,7 @@ let max_int = min_int - 1
 (* Floating-point operations *)
 
 external (~-.) : float -> float = "%negfloat"
+external (~+.) : float -> float = "%identity"
 external (+.) : float -> float -> float = "%addfloat"
 external (-.) : float -> float -> float = "%subfloat"
 external ( *. ) : float -> float -> float = "%mulfloat"
diff --git a/stdlib/pervasives.mli b/stdlib/pervasives.mli
index d77b44249..da5a5aa49 100644
--- a/stdlib/pervasives.mli
+++ b/stdlib/pervasives.mli
@@ -145,13 +145,16 @@ external ( or ) : bool -> bool -> bool = "%sequor"
    They do not fail on overflow. *)
 
 external ( ~- ) : int -> int = "%negint"
-(** Unary negation. You can also write [-e] instead of [~-e]. *)
+(** Unary negation. You can also write [- e] instead of [~- e]. *)
+
+external ( ~+ ) : int -> int = "%identity"
+(** Unary addition. You can also write [+ e] instead of [~+ e]. *)
 
 external succ : int -> int = "%succint"
-(** [succ x] is [x+1]. *)
+(** [succ x] is [x + 1]. *)
 
 external pred : int -> int = "%predint"
-(** [pred x] is [x-1]. *)
+(** [pred x] is [x - 1]. *)
 
 external ( + ) : int -> int -> int = "%addint"
 (** Integer addition. *)
@@ -168,7 +171,7 @@ external ( / ) : int -> int -> int = "%divint"
    Integer division rounds the real quotient of its arguments towards zero.
    More precisely, if [x >= 0] and [y > 0], [x / y] is the greatest integer
    less than or equal to the real quotient of [x] by [y].  Moreover,
-   [(-x) / y = x / (-y) = -(x / y)].  *)
+   [(- x) / y = x / (-y) = - (x / y)].  *)
 
 external ( mod ) : int -> int -> int = "%modint"
 (** Integer remainder.  If [y] is not zero, the result
@@ -237,7 +240,10 @@ external ( asr ) : int -> int -> int = "%asrint"
 *)
 
 external ( ~-. ) : float -> float = "%negfloat"
-(** Unary negation. You can also write [-.e] instead of [~-.e]. *)
+(** Unary negation. You can also write [-. e] instead of [~-. e]. *)
+
+external ( ~+. ) : float -> float = "%identity"
+(** Unary addition. You can also write [+. e] instead of [~+. e]. *)
 
 external ( +. ) : float -> float -> float = "%addfloat"
 (** Floating-point addition *)