Merge pull request #315 from alainfrisch/all_clause_guarded_warning

"All clauses guarded" warning (25) now part of standard "non exhaustive" warning (8)

Changes

@@ -78,6 +78,8 @@ Compilers:
 - PR#6845: -no-check-prims to tell ocamlc not to check primitives in runtime
 * PR#6865: remove special case for parsing "let _ = expr" in structures
   (Jérémie Dimino, Alain Frisch)
+* PR#6438: Pattern guard disables exhaustiveness check
+  (Alain Frisch)
 - PR#6939: Segfault with improper use of let-rec (Alain Frisch)
 - PR#6943: native-code generator for POWER/PowerPC 64 bits, both in
   big-endian (ppc64) and little-endian (ppc64le) configuration.

testsuite/tests/typing-warnings/exhaustiveness.ml

@@ -103,3 +103,7 @@ let f () = match None with _ -> .;; (* error *)
 let g () = match None with _ -> () | exception _ -> .;; (* error *)
 let h () = match None with _ -> .  | exception _ -> .;; (* error *)
 let f x = match x with _ -> () | None -> .;; (* do not warn *)
+
+(* #7059, all clauses guarded *)
+
+let f x y = match 1 with 1 when x = y -> 1;;

testsuite/tests/typing-warnings/exhaustiveness.ml.reference

@@ -113,4 +113,10 @@ Error: This match case could not be refuted.
 Error: This match case could not be refuted.
        Here is an example of a value that would reach it: _
 # val f : 'a option -> unit = <fun>
+#       Characters 47-77:
+  let f x y = match 1 with 1 when x = y -> 1;;
+              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Warning 8: this pattern-matching is not exhaustive.
+All clauses in this pattern-matching are guarded.
+val f : 'a -> 'a -> int = <fun>
 # 

utils/warnings.ml

@@ -42,7 +42,7 @@ type t =
   | Preprocessor of string                  (* 22 *)
   | Useless_record_with                     (* 23 *)
   | Bad_module_name of string               (* 24 *)
-  | All_clauses_guarded                     (* 25 *)
+  | All_clauses_guarded                     (* 8, used to be 25 *)
   | Unused_var of string                    (* 26 *)
   | Unused_var_strict of string             (* 27 *)
   | Wildcard_arg_to_constant_constr         (* 28 *)
@@ -107,7 +107,7 @@ let number = function
   | Preprocessor _ -> 22
   | Useless_record_with -> 23
   | Bad_module_name _ -> 24
-  | All_clauses_guarded -> 25
+  | All_clauses_guarded -> 8 (* used to be 25 *)
   | Unused_var _ -> 26
   | Unused_var_strict _ -> 27
   | Wildcard_arg_to_constant_constr -> 28
@@ -171,7 +171,7 @@ let letter = function
   | 'u' -> [11; 12]
   | 'v' -> [13]
   | 'w' -> []
-  | 'x' -> [14; 15; 16; 17; 18; 19; 20; 21; 22; 23; 24; 25; 30]
+  | 'x' -> [14; 15; 16; 17; 18; 19; 20; 21; 22; 23; 24; 30]
   | 'y' -> [26]
   | 'z' -> [27]
   | _ -> assert false
@@ -324,7 +324,8 @@ let message = function
   | Bad_module_name (modname) ->
       "bad source file name: \"" ^ modname ^ "\" is not a valid module name."
   | All_clauses_guarded ->
-      "bad style, all clauses in this pattern-matching are guarded."
+      "this pattern-matching is not exhaustive.\n\
+       All clauses in this pattern-matching are guarded."
   | Unused_var v | Unused_var_strict v -> "unused variable " ^ v ^ "."
   | Wildcard_arg_to_constant_constr ->
      "wildcard pattern given as argument to a constant constructor"
@@ -482,8 +483,8 @@ let descriptions =
    23, "Useless record \"with\" clause.";
    24, "Bad module name: the source file name is not a valid OCaml module \
         name.";
-   25, "Pattern-matching with all clauses guarded.  Exhaustiveness cannot be\n\
-   \    checked.";
+   (* 25, "Pattern-matching with all clauses guarded.  Exhaustiveness cannot be\n\
+   \    checked.";  (* Now part of warning 8 *) *)
    26, "Suspicious unused variable: unused variable that is bound\n\
    \    with \"let\" or \"as\", and doesn't start with an underscore (\"_\")\n\
    \    character.";