Add warning for unused labels

man/ocamlc.m

@@ -1025,7 +1025,7 @@ compilation in any way (even if it is fatal).  If a warning is enabled,
 
 .IP
 The default setting is
-.BR \-w\ +a\-4\-6\-7\-9\-27\-29\-30\-32..42\-44\-45\-48\-50\-60\-66\-67\-68 .
+.BR \-w\ +a\-4\-6\-7\-9\-27\-29\-30\-32..42\-44\-45\-48\-50\-60\-66..69 .
 Note that warnings
 .BR 5 \ and \ 10
 are not always triggered, depending on the internals of the type checker.

testsuite/tests/typing-warnings/unused_types.ml

@@ -353,6 +353,14 @@ module Unused_record : sig end = struct
   let _ = foo
 end;;
 [%%expect {|
+Line 2, characters 13-21:
+2 |   type t = { a : int; b : int }
+                 ^^^^^^^^
+Warning 69 [unused-field]: unused record field a.
+Line 2, characters 22-29:
+2 |   type t = { a : int; b : int }
+                          ^^^^^^^
+Warning 69 [unused-field]: unused record field b.
 module Unused_record : sig end
 |}]
 
@@ -362,6 +370,11 @@ module Unused_field : sig end = struct
   let _ = foo
 end;;
 [%%expect {|
+Line 2, characters 13-20:
+2 |   type t = { a : int }
+                 ^^^^^^^
+Warning 69 [unused-field]: record field a is never read.
+(However, this field is used to build or mutate values.)
 module Unused_field : sig end
 |}]
 
@@ -373,6 +386,11 @@ module Unused_field : sig end = struct
   let _ = foo, bar, baz
 end;;
 [%%expect {|
+Line 2, characters 22-30:
+2 |   type t = { a : int; b : int; c : int }
+                          ^^^^^^^^
+Warning 69 [unused-field]: record field b is never read.
+(However, this field is used to build or mutate values.)
 module Unused_field : sig end
 |}]
 
@@ -383,6 +401,10 @@ module Unused_mutable_field : sig end = struct
   let _ = foo, bar
 end;;
 [%%expect {|
+Line 2, characters 22-37:
+2 |   type t = { a : int; mutable b : int }
+                          ^^^^^^^^^^^^^^^
+Warning 69 [unused-field]: mutable record field b is never mutated.
 module Unused_mutable_field : sig end
 |}]
 
@@ -414,6 +436,10 @@ end = struct
   let _ = foo
 end;;
 [%%expect {|
+Line 4, characters 22-37:
+4 |   type t = { a : int; mutable b : int }
+                          ^^^^^^^^^^^^^^^
+Warning 69 [unused-field]: mutable record field b is never mutated.
 module Unused_mutable_field_exported_private :
   sig type t = private { a : int; mutable b : int; } end
 |}]

toplevel/native/topeval.ml

@@ -156,7 +156,7 @@ let load_lambda ppf ~module_ident ~required_globals lam size =
     else Closure_middle_end.lambda_to_clambda
   in
   Asmgen.compile_implementation ~toplevel:need_symbol
-    ~backend ~filename ~prefixname:filename
+    ~backend ~prefixname:filename
     ~middle_end ~ppf_dump:ppf program;
   Asmlink.call_linker_shared [filename ^ ext_obj] dll;
   Sys.remove (filename ^ ext_obj);