[BetterEngineering] Remove remaining uses of polymorphic equality

Summary:
Remove the remaining uses of polymorphic equality `=`.
In case of basic types, this is replaced by String.equal or Int.equal.
In case of `= []`, this is replaced by `List.is_empty`.
In case of `= None`, this is replaced by `is_none`.
In case of a datatype definition such as `type a = A | B`,
a `compare_a` function is defined by adding `type a = A | B [@deriving compare]`
and a `equal_a` function is defined as `let equal_a = [%compare.equal : a]`.
In case of comparison with a polymorphic variant `= `Yes`, the equality
defined in `PVariant.(=)` is used. Typically, `open! Pvariant` is added
at the beginning of the file to cover all the uses.

Reviewed By: jberdine

Differential Revision: D4456129

fbshipit-source-id: f31c433

infer/src/IR/PredSymb.re

@@ -28,6 +28,8 @@ type access =
   | Protected
 [@@deriving compare];
 
+let equal_access = [%compare.equal : access];
+
 
 /** Return the value of the FA_sentinel attribute in [attr_list] if it is found */
 let get_sentinel_func_attribute_value attr_list =>

infer/src/IR/PredSymb.rei

@@ -34,6 +34,8 @@ type access =
   | Protected
 [@@deriving compare];
 
+let equal_access: access => access => bool;
+
 type mem_kind =
   | Mmalloc /** memory allocated with malloc */
   | Mnew /** memory allocated with new */

infer/src/IR/Procdesc.re

@@ -17,7 +17,8 @@ let module F = Format;
 
 /* =============== START of module Node =============== */
 let module Node = {
-  type id = int;
+  type id = int [@@deriving compare];
+  let equal_id = [%compare.equal : id];
   type nodekind =
     | Start_node Procname.t
     | Exit_node Procname.t
@@ -26,6 +27,7 @@ let module Node = {
     | Prune_node bool Sil.if_kind string /** (true/false branch, if_kind, comment) */
     | Skip_node string
   [@@deriving compare];
+  let equal_nodekind = [%compare.equal : nodekind];
 
   /** a node */
   type t = {
@@ -68,9 +70,6 @@ let module Node = {
 
   /** Get the unique id of the node */
   let get_id node => node.id;
-
-  /** compare node ids */
-  let compare_id = Int.compare;
   let get_succs node => node.succs;
   type node = t;
   let module NodeSet = Caml.Set.Make {

infer/src/IR/Procdesc.rei

@@ -18,6 +18,7 @@ let module Node: {
 
   /** node id */
   type id = private int [@@deriving compare];
+  let equal_id: id => id => bool;
 
   /** kind of cfg node */
   type nodekind =
@@ -28,6 +29,7 @@ let module Node: {
     | Prune_node bool Sil.if_kind string /** (true/false branch, if_kind, comment) */
     | Skip_node string
   [@@deriving compare];
+  let equal_nodekind: nodekind => nodekind => bool;
 
   /** kind of Stmt_node for an exception handler. */
   let exn_handler_kind: nodekind;

infer/src/IR/Sil.re

@@ -2094,7 +2094,7 @@ let compare_structural_instr instr1 instr2 exp_map => {
     }
   };
   let id_list_compare_structural ids1 ids2 exp_map => {
-    let n = Pervasives.compare (IList.length ids1) (IList.length ids2);
+    let n = Int.compare (IList.length ids1) (IList.length ids2);
     if (n != 0) {
       (n, exp_map)
     } else {
@@ -2150,14 +2150,14 @@ let compare_structural_instr instr1 instr2 exp_map => {
         if (n != 0) {
           n
         } else {
-          Pervasives.compare ik1 ik2
+          compare_if_kind ik1 ik2
         }
       },
       exp_map
     )
   | (Call ret_id1 e1 arg_ts1 _ cf1, Call ret_id2 e2 arg_ts2 _ cf2) =>
     let args_compare_structural args1 args2 exp_map => {
-      let n = Pervasives.compare (IList.length args1) (IList.length args2);
+      let n = Int.compare (IList.length args1) (IList.length args2);
       if (n != 0) {
         (n, exp_map)
       } else {
@@ -2199,7 +2199,7 @@ let compare_structural_instr instr1 instr2 exp_map => {
   | (Remove_temps temps1 _, Remove_temps temps2 _) =>
     id_list_compare_structural temps1 temps2 exp_map
   | (Declare_locals ptl1 _, Declare_locals ptl2 _) =>
-    let n = Pervasives.compare (IList.length ptl1) (IList.length ptl2);
+    let n = Int.compare (IList.length ptl1) (IList.length ptl2);
     if (n != 0) {
       (n, exp_map)
     } else {

infer/src/IR/Typ.re

@@ -108,6 +108,8 @@ type ptr_kind =
   | Pk_objc_autoreleasing /** Obj-C __autoreleasing pointer */
 [@@deriving compare];
 
+let equal_ptr_kind = [%compare.equal : ptr_kind];
+
 let ptr_kind_string =
   fun
   | Pk_reference => "&"

infer/src/IR/Typ.rei

@@ -63,6 +63,8 @@ type ptr_kind =
   | Pk_objc_autoreleasing /** Obj-C __autoreleasing pointer */
 [@@deriving compare];
 
+let equal_ptr_kind: ptr_kind => ptr_kind => bool;
+
 
 /** statically determined length of an array type, if any */
 type static_length = option IntLit.t [@@deriving compare];

infer/src/backend/BuiltinDefn.ml

@@ -699,7 +699,7 @@ let _execute_free_nonzero mk pdesc tenv instr prop lexp typ loc =
           IList.rev prop_list
     end
   with Rearrange.ARRAY_ACCESS ->
-    if (Config.array_level = 0) then assert false
+    if (Int.equal Config.array_level 0) then assert false
     else begin
       L.d_strln ".... Array containing allocated heap cells ....";
       L.d_str "  Instr: "; Sil.d_instr instr; L.d_ln ();
@@ -929,8 +929,8 @@ let execute___infer_fail { Builtin.pdesc; tenv; prop_; path; args; loc; }
 let execute___assert_fail { Builtin.pdesc; tenv; prop_; path; args; loc; }
   : Builtin.ret_typ =
   let error_str =
-    match args with
+    match IList.length args with
-    | l when IList.length l = 4 ->
+    | 4 ->
         Config.default_failure_name
     | _ ->
         raise (Exceptions.Wrong_argument_number __POS__) in

infer/src/backend/dom.ml

@@ -251,7 +251,7 @@ module CheckJoinPre : InfoLossCheckerSig = struct
     | Exp.Lvar _ -> false
     | Exp.Var id when Ident.is_normal id -> IList.length es >= 1
     | Exp.Var _ ->
-        if Config.join_cond = 0 then
+        if Int.equal Config.join_cond 0 then
           IList.exists (Exp.equal Exp.zero) es
         else if Dangling.check side e then
           begin
@@ -989,7 +989,7 @@ and dynamic_length_partial_join l1 l2 =
   option_partial_join (fun len1 len2 -> Some (length_partial_join len1 len2)) l1 l2
 
 and typ_partial_join t1 t2 = match t1, t2 with
-  | Typ.Tptr (t1, pk1), Typ.Tptr (t2, pk2) when Typ.compare_ptr_kind pk1 pk2 = 0 ->
+  | Typ.Tptr (t1, pk1), Typ.Tptr (t2, pk2) when Typ.equal_ptr_kind pk1 pk2 ->
       Typ.Tptr (typ_partial_join t1 t2, pk1)
   | Typ.Tarray (typ1, len1), Typ.Tarray (typ2, len2) ->
       let t = typ_partial_join typ1 typ2 in
@@ -1069,7 +1069,7 @@ let rec strexp_partial_join mode (strexp1: Sil.strexp) (strexp2: Sil.strexp) : S
         end
     | (fld1, se1):: fld_se_list1', (fld2, se2):: fld_se_list2' ->
         let comparison = Ident.compare_fieldname fld1 fld2 in
-        if comparison = 0 then
+        if Int.equal comparison 0 then
           let strexp' = strexp_partial_join mode se1 se2 in
           let fld_se_list_new = (fld1, strexp') :: acc in
           f_fld_se_list inst mode fld_se_list_new fld_se_list1' fld_se_list2'
@@ -1633,7 +1633,7 @@ let pi_partial_join tenv mode
     match Rename.get_other_atoms tenv side a with
     | None -> None
     | Some (a_res, a_op) ->
-        if mode = JoinState.Pre then join_atom_check_pre p_op a_op;
+        if JoinState.equal_mode mode JoinState.Pre then join_atom_check_pre p_op a_op;
         if Attribute.is_pred a then join_atom_check_attribute p_op a_op;
         if not (Prover.check_atom tenv p_op a_op) then None
         else begin
@@ -1756,7 +1756,7 @@ let eprop_partial_join' tenv mode (ep1: Prop.exposed Prop.t) (ep2: Prop.exposed
   let es1 = sigma_get_start_lexps_sort sigma1 in
   let es2 = sigma_get_start_lexps_sort sigma2 in
 
-  let simple_check = IList.length es1 = IList.length es2 in
+  let simple_check = Int.equal (IList.length es1) (IList.length es2) in
   let rec expensive_check es1' es2' =
     match (es1', es2') with
     | [], [] -> true
@@ -2017,7 +2017,7 @@ let proplist_meet_generate tenv plist =
 
 let propset_meet_generate_pre tenv pset =
   let plist = Propset.to_proplist pset in
-  if Config.meet_level = 0 then plist
+  if Int.equal Config.meet_level 0 then plist
   else
     let pset1 = proplist_meet_generate tenv plist in
     let pset_new = Propset.diff pset1 pset in

infer/src/backend/interproc.ml

@@ -9,6 +9,8 @@
  *)
 
 open! IStd
+open! PVariant
+
 module Hashtbl = Caml.Hashtbl
 
 (** Interprocedural Analysis *)
@@ -529,7 +531,7 @@ let forward_tabulate tenv pdesc wl source =
     let log_string proc_name =
       let summary = Specs.get_summary_unsafe "forward_tabulate" proc_name in
       let phase_string =
-        if Specs.get_phase summary = Specs.FOOTPRINT then "FP" else "RE" in
+        if Specs.equal_phase (Specs.get_phase summary) Specs.FOOTPRINT then "FP" else "RE" in
       let timestamp = Specs.get_timestamp summary in
       F.sprintf "[%s:%d] %s" phase_string timestamp (Procname.to_string proc_name) in
     L.d_strln ("**** " ^ (log_string pname) ^ " " ^
@@ -1174,14 +1176,14 @@ let is_unavoidable tenv pre =
 let report_runtime_exceptions tenv pdesc summary =
   let pname = Specs.get_proc_name summary in
   let is_public_method =
-    (Specs.get_attributes summary).ProcAttributes.access = PredSymb.Public in
+    PredSymb.equal_access (Specs.get_attributes summary).access PredSymb.Public in
   let is_main =
     is_public_method
     &&
     (match pname with
      | Procname.Java pname_java ->
          Procname.java_is_static pname
-         && (Procname.java_get_method pname_java) = "main"
+         && String.equal (Procname.java_get_method pname_java) "main"
      | _ ->
          false) in
   let is_annotated =
@@ -1235,7 +1237,7 @@ let update_specs tenv proc_name phase (new_specs : Specs.NormSpec.t list)
               (Paths.PathSet.from_renamed_list spec.Specs.posts, spec.Specs.visited) map)
          SpecMap.empty old_specs) in
   let re_exe_filter old_spec = (* filter out pres which failed re-exe *)
-    if phase = Specs.RE_EXECUTION &&
+    if Specs.equal_phase phase Specs.RE_EXECUTION &&
        not (IList.exists
               (fun new_spec -> Specs.Jprop.equal new_spec.Specs.pre old_spec.Specs.pre)
               new_specs)
@@ -1395,7 +1397,7 @@ let perform_transition exe_env tenv proc_name source =
         [] in
     transition_footprint_re_exe tenv proc_name joined_pres in
   match Specs.get_summary proc_name with
-  | Some summary when Specs.get_phase summary = Specs.FOOTPRINT ->
+  | Some summary when Specs.equal_phase (Specs.get_phase summary) Specs.FOOTPRINT ->
       transition ()
   | _ -> ()
 
@@ -1404,7 +1406,7 @@ let interprocedural_algorithm exe_env : unit =
   let call_graph = Exe_env.get_cg exe_env in
   let filter_initial proc_name =
     let summary = Specs.get_summary_unsafe "main_algorithm" proc_name in
-    Specs.get_timestamp summary = 0 in
+    Int.equal (Specs.get_timestamp summary) 0 in
   let procs_to_analyze =
     IList.filter filter_initial (Cg.get_defined_nodes call_graph) in
   let to_analyze proc_name =
@@ -1461,7 +1463,7 @@ let do_analysis exe_env =
     (fun ((pn, _) as x) ->
        let should_init () =
          Config.models_mode ||
-         Specs.get_summary pn = None in
+         is_none (Specs.get_summary pn) in
        if should_init ()
        then init_proc x)
     procs_and_defined_children;
@@ -1547,7 +1549,7 @@ let print_stats_cfg proc_shadowed source cfg =
   let compute_stats_proc proc_desc =
     let proc_name = Procdesc.get_proc_name proc_desc in
     if proc_shadowed proc_desc ||
-       Specs.get_summary proc_name = None then
+       is_none (Specs.get_summary proc_name) then
       L.out "print_stats: ignoring function %a which is also defined in another file@."
         Procname.pp proc_name
     else
@@ -1560,7 +1562,8 @@ let print_stats_cfg proc_shadowed source cfg =
       let () =
         match specs,
               Errlog.size
-                (fun ekind in_footprint -> ekind = Exceptions.Kerror && in_footprint)
+                (fun ekind in_footprint ->
+                   Exceptions.equal_err_kind ekind Exceptions.Kerror && in_footprint)
                 err_log with
         | [], 0 -> incr num_nospec_noerror_proc
         | _, 0 -> incr num_spec_noerror_proc

infer/src/backend/joinState.ml

@@ -14,6 +14,9 @@ open! IStd
 type mode =
   | Pre
   | Post
+[@@deriving compare]
+
+let equal_mode = [%compare.equal : mode]
 
 (** set to true when we are doing join of footprints *)
 let footprint = ref false

infer/src/backend/joinState.mli

@@ -14,6 +14,9 @@ open! IStd
 type mode =
   | Pre
   | Post
+[@@deriving compare]
+
+val equal_mode : mode -> mode -> bool
 
 val get_footprint : unit -> bool
 val set_footprint : bool -> unit

infer/src/backend/specs.mli

@@ -119,6 +119,8 @@ type status = ACTIVE | INACTIVE | STALE
 
 type phase = FOOTPRINT | RE_EXECUTION
 
+val equal_phase : phase -> phase -> bool
+
 type dependency_map_t = int Procname.Map.t
 
 type call_summary = CallSite.Set.t Annot.Map.t

infer/src/base/IStd.ml

@@ -52,7 +52,7 @@ module IntSet = Caml.Set.Make(Int)
 (* Compare police: generic compare mostly disabled. *)
 let compare = No_polymorphic_compare.compare
 let equal = No_polymorphic_compare.equal
-(* let (=) = equal *)
+let (=) = No_polymorphic_compare.(=)
 
 module PVariant = struct
   (* Equality for polymorphic variants *)

infer/src/checkers/BoundedCallTree.ml

@@ -124,7 +124,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
             | Procname.C _ -> true (* Needed for test code. *)
             | Procname.Block _ | Procname.Linters_dummy_method ->
                 failwith "Proc type not supported by crashcontext: block" in
-          frame.Stacktrace.method_str = (Procname.get_method caller) &&
+          String.equal frame.Stacktrace.method_str (Procname.get_method caller) &&
           matches_class caller in
         let all_frames = IList.flatten
             (IList.map (fun trace -> trace.Stacktrace.frames) traces) in

infer/src/checkers/SimpleChecker.ml

@@ -95,7 +95,7 @@ module Make (Spec : Spec) : S = struct
         (* should never fail since keys in the invariant map should always be real node id's *)
         let node =
           IList.find
-            (fun node -> Procdesc.Node.compare_id node_id (Procdesc.Node.get_id node) = 0)
+            (fun node -> Procdesc.Node.equal_id node_id (Procdesc.Node.get_id node))
             nodes in
         Domain.iter
           (fun astate ->

infer/src/checkers/ThreadSafety.ml

@@ -388,7 +388,9 @@ let is_immutable_collection_class class_name tenv =
     "com.google.common.collect.ImmutableTable";
   ] in
   PatternMatch.supertype_exists
-    tenv (fun typename _ -> IList.mem (=) (Typename.name typename) immutable_collections) class_name
+    tenv
+    (fun typename _ -> IList.mem String.equal (Typename.name typename) immutable_collections)
+    class_name
 
 let is_call_to_builder_class_method = function
   | Procname.Java java_pname -> is_builder_class (Procname.java_get_class_name java_pname)
@@ -560,7 +562,7 @@ let should_report_on_file file_env =
     fun (_, tenv, pname, _) ->
       match get_current_class_and_threadsafe_superclasses tenv pname with
       | Some (_, thread_safe_annotated_classes) ->
-          not (thread_safe_annotated_classes = [])
+          not (List.is_empty thread_safe_annotated_classes)
       | _ -> false
   in
   let current_class_marked_not_threadsafe =

infer/src/checkers/ThreadSafetyDomain.ml

@@ -49,7 +49,7 @@ module PathDomain = SinkTrace.Make(TraceElem)
 
 module IntMap = PrettyPrintable.MakePPMap(struct
     type t = int
-    let compare = Pervasives.compare
+    let compare = Int.compare
     let pp_key fmt = F.fprintf fmt "%d"
   end)
 

infer/src/checkers/Trace.ml

@@ -288,7 +288,7 @@ module Make (Spec : Spec) = struct
           (fun passthrough1 passthrough2 ->
              let loc1 = CallSite.loc (Passthrough.site passthrough1) in
              let loc2 = CallSite.loc (Passthrough.site passthrough2) in
-             Pervasives.compare loc1.Location.line loc2.Location.line)
+             Int.compare loc1.Location.line loc2.Location.line)
           (Passthroughs.elements passthroughs) in
       IList.fold_right trace_elem_of_passthrough sorted_passthroughs acc0 in
 

infer/src/checkers/annotationReachability.ml

@@ -194,7 +194,7 @@ let report_allocation_stack
   Reporting.log_error pname ~loc:fst_call_loc ~ltr:final_trace exn
 
 let report_annotation_stack src_annot snk_annot src_pname loc trace stack_str snk_pname call_loc =
-  if snk_annot = dummy_constructor_annot
+  if String.equal snk_annot dummy_constructor_annot
   then report_allocation_stack src_annot src_pname loc trace stack_str snk_pname call_loc
   else
     let final_trace = IList.rev (update_trace call_loc trace) in
@@ -209,7 +209,7 @@ let report_annotation_stack src_annot snk_annot src_pname loc trace stack_str sn
         exp_pname_str
         snk_annot in
     let msg =
-      if src_annot = Annotations.performance_critical
+      if String.equal src_annot Annotations.performance_critical
       then calls_expensive_method
       else annotation_reachability_error in
     let exn =
@@ -259,7 +259,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
   let is_unlikely pname =
     match pname with
     | Procname.Java java_pname ->
-        (Procname.java_get_method java_pname) = "unlikely"
+        String.equal (Procname.java_get_method java_pname) "unlikely"
     | _ -> false
 
   let is_tracking_exp astate = function
@@ -283,7 +283,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
   (* TODO: generalize this to allow sanitizers for other annotation types, store it in [extras] so
      we can compute it just once *)
   let method_is_sanitizer annot tenv pname =
-    if annot.Annot.class_name = dummy_constructor_annot
+    if String.equal annot.Annot.class_name dummy_constructor_annot
     then method_has_ignore_allocation_annot tenv pname
     else false
 
@@ -393,7 +393,7 @@ module Interprocedural = struct
             (CallSite.make proc_name loc)
             calls in
       let calls = extract_calls_with_annot snk_annot call_map in
-      if not (IList.length calls = 0)
+      if not (Int.equal (IList.length calls) 0)
       then IList.iter (report_src_snk_path calls) src_annot_list in
 
     let initial =

infer/src/checkers/checkDeadCode.ml

@@ -83,7 +83,7 @@ let check_final_state tenv proc_name proc_desc final_s =
         let description = Format.sprintf "Node not visited: %d" (Procdesc.Node.get_id n :> int) in
         let report = match Procdesc.Node.get_kind n with
           | Procdesc.Node.Join_node -> false
-          | k when k = Procdesc.Node.exn_sink_kind -> false
+          | k when Procdesc.Node.equal_nodekind k Procdesc.Node.exn_sink_kind -> false
           | _ -> true in
         if report
         then report_error tenv description proc_name proc_desc loc in

infer/src/checkers/checkTraceCallSequence.ml

@@ -47,13 +47,13 @@ module APIs = struct
   let method_match pn pkgname cname mname =
     match pn with
     | Procname.Java pn_java ->
-        Procname.java_get_method pn_java = mname
+        String.equal (Procname.java_get_method pn_java) mname
         &&
         (match pkgname with
          | "" ->
-             Procname.java_get_simple_class_name pn_java = cname
+             String.equal (Procname.java_get_simple_class_name pn_java) cname
          | _ ->
-             Procname.java_get_class_name pn_java = pkgname ^ "." ^ cname)
+             String.equal (Procname.java_get_class_name pn_java) (pkgname ^ "." ^ cname))
     | _ ->
         false
   let is_begin pn =
@@ -113,11 +113,11 @@ module State = struct
 
   (** State is balanced. *)
   let is_balanced s =
-    ElemSet.for_all (fun elem -> Elem.get_int elem = 0) s
+    ElemSet.for_all (fun elem -> Int.equal (Elem.get_int elem) 0) s
 
   let equal = ElemSet.equal
 
-  let has_zero s = ElemSet.exists (fun elem -> Elem.get_int elem = 0) s
+  let has_zero s = ElemSet.exists (fun elem -> Int.equal (Elem.get_int elem) 0) s
 
   (** Map a function to the elements of the set, and filter out inconsistencies. *)
   let map2 (f : Elem.t -> Elem.t list) (s : t) : t =

infer/src/checkers/fragmentRetainsViewChecker.ml

@@ -24,7 +24,7 @@ let callback_fragment_retains_view_java
     pname_java { Callbacks.proc_desc; tenv } =
   (* TODO: complain if onDestroyView is not defined, yet the Fragment has View fields *)
   (* TODO: handle fields nullified in callees in the same file *)
-  let is_on_destroy_view = Procname.java_get_method pname_java = "onDestroyView" in
+  let is_on_destroy_view = String.equal (Procname.java_get_method pname_java) "onDestroyView" in
   let fld_typ_is_view = function
     | Typ.Tptr (Tstruct tname, _) -> AndroidFramework.is_view tenv tname
     | _ -> false in

infer/src/checkers/repeatedCallsChecker.ml

@@ -56,6 +56,9 @@ struct
   type paths =
     | AllPaths (** Check on all paths *)
     | SomePath (** Check if some path exists *)
+  [@@deriving compare]
+
+  let equal_paths = [%compare.equal : paths]
 
   (** Check if the procedure performs an allocation operation.
       If [paths] is AllPaths, check if an allocation happens on all paths.
@@ -77,21 +80,21 @@ struct
 
     let module DFAllocCheck = Dataflow.MakeDF(struct
         type t = Location.t option [@@deriving compare]
-        let equal x y = compare x y = 0
+        let equal = [%compare.equal : t]
-        let _join _paths l1o l2o = (* join with left priority *)
+        let join_ paths_ l1o l2o = (* join with left priority *)
           match l1o, l2o with
           | None, None ->
               None
           | Some loc, None
           | None, Some loc ->
-              if _paths = AllPaths then None else Some loc
+              if equal_paths paths_ AllPaths then None else Some loc
           | Some loc1, Some _ ->
               Some loc1 (* left priority *)
-        let join = _join paths
+        let join = join_ paths
         let do_node _ node lo1 =
           let lo2 = node_allocates node in
           let lo' = (* use left priority join to implement transfer function *)
-            _join SomePath lo1 lo2 in
+            join_ SomePath lo1 lo2 in
           [lo'], [lo']
         let proc_throws _ = Dataflow.DontKnow
       end) in

infer/src/checkers/sqlChecker.ml

@@ -29,8 +29,8 @@ let callback_sql { Callbacks.proc_desc; proc_name; tenv } =
   (* Check for SQL string concatenations *)
   let do_instr const_map node instr =
     let do_call pn_java i1 i2 l =
-      if Procname.java_get_class_name pn_java = "java.lang.StringBuilder"
+      if String.equal (Procname.java_get_class_name pn_java) "java.lang.StringBuilder"
-      && Procname.java_get_method pn_java = "append"
+      && String.equal (Procname.java_get_method pn_java) "append"
       then
         begin
           let rvar1 = Exp.Var i1 in

infer/src/clang/CType_decl.ml

@@ -180,7 +180,7 @@ and get_record_declaration_struct_type tenv decl =
           [StructTyp.objc_ref_counter_field]
         else [] in
       let annots =
-        if csu = Csu.Class Csu.CPP then Annot.Class.cpp
+        if Csu.equal csu (Csu.Class Csu.CPP) then Annot.Class.cpp
         else Annot.Item.empty (* No annotations for structs *) in
       if is_complete_definition then (
         CAst_utils.update_sil_types_map type_ptr (Typ.Tstruct sil_typename);

infer/src/clang/Capture.re

@@ -158,7 +158,10 @@ let cc1_capture clang_cmd => {
     Utils.filename_to_absolute root::root orig_argv.(Array.length orig_argv - 1)
   };
   Logging.out "@\n*** Beginning capture of file %s ***@\n" source_path;
-  if (Config.analyzer == Config.Compile || CLocation.is_file_blacklisted source_path) {
+  if (
+    Config.equal_analyzer Config.analyzer Config.Compile ||
+    CLocation.is_file_blacklisted source_path
+  ) {
     Logging.out "@\n Skip the analysis of source file %s@\n@\n" source_path;
     /* We still need to run clang, but we don't have to attach the plugin. */
     run_clang (ClangCommand.command_to_run clang_cmd) Utils.consume_in

infer/src/clang/ClangWrapper.re

@@ -105,8 +105,8 @@ let exe prog::prog args::args => {
     | None => (clang_xx, false)
     };
   IList.iter exec_action_item commands;
-  if (commands == [] || should_run_original_command) {
+  if (List.is_empty commands || should_run_original_command) {
-    if (commands == []) {
+    if (List.is_empty commands) {
       /* No command to execute after -###, let's execute the original command
          instead.
 

infer/src/clang/ComponentKit.ml

@@ -8,6 +8,7 @@
  *)
 
 open! IStd
+open! PVariant
 
 let get_source_range an =
   match an with
@@ -231,7 +232,7 @@ let component_with_multiple_factory_methods_advice context an =
       | ObjCMethodDecl (decl_info, _, _) -> decl_info.Clang_ast_t.di_attributes
       | _ -> assert false in
     let unavailable_attrs = (IList.filter is_unavailable_attr attrs) in
-    let is_available = IList.length unavailable_attrs = 0 in
+    let is_available = Int.equal (IList.length unavailable_attrs) 0 in
     (CAst_utils.is_objc_factory_method if_decl decl) && is_available in
 
   let check_interface if_decl =

infer/src/clang/cAst_utils.ml

@@ -8,6 +8,7 @@
  *)
 
 open! IStd
+open! PVariant
 
 (** Functions for transformations of ast nodes *)
 
@@ -105,15 +106,6 @@ let generated_ivar_name property_name =
       }
   | _ -> make_name_decl property_name.Clang_ast_t.ni_name
 
-let compare_property_attribute =
-  [%compare: [
-    `Readonly | `Assign | `Readwrite | `Retain | `Copy | `Nonatomic | `Atomic
-    | `Weak | `Strong | `Unsafe_unretained | `ExplicitGetter | `ExplicitSetter
-  ]]
-
-let equal_property_attribute att1 att2 =
-  compare_property_attribute att1 att2 = 0
-
 let get_memory_management_attributes () =
   [`Assign; `Retain; `Copy; `Weak; `Strong; `Unsafe_unretained]
 
@@ -235,8 +227,10 @@ let get_decl_from_typ_ptr typ_ptr =
 let is_type_nonnull type_ptr =
   let open Clang_ast_t in
   match get_type type_ptr with
-  | Some AttributedType (_, attr_info) -> attr_info.ati_attr_kind = `Nonnull
+  | Some AttributedType (_, attr_info) ->
-  | _ -> false
+      attr_info.ati_attr_kind = `Nonnull
+  | _ ->
+      false
 
 let is_type_nullable type_ptr =
   let open Clang_ast_t in
@@ -283,7 +277,7 @@ let get_function_decl_with_body decl_ptr =
     | Some (CXXDestructorDecl (_, _, _, fdecl_info, _)) ->
         fdecl_info.Clang_ast_t.fdi_decl_ptr_with_body
     | _ -> Some decl_ptr in
-  if decl_ptr' = (Some decl_ptr) then decl_opt
+  if [%compare.equal : int option] decl_ptr' (Some decl_ptr) then decl_opt
   else get_decl_opt decl_ptr'
 
 let get_info_from_decl_ref decl_ref =
@@ -317,7 +311,7 @@ let is_ptr_to_objc_class typ class_name =
        | Some ObjCInterfaceType (_, ptr) ->
            (match get_decl ptr with
             | Some ObjCInterfaceDecl (_, ndi, _, _, _) ->
-                String.compare ndi.ni_name class_name = 0
+                String.equal ndi.ni_name class_name
             | _ -> false)
        | _ -> false)
   | _ -> false
@@ -442,7 +436,7 @@ let if_decl_to_di_pointer_opt if_decl =
 
 let is_instance_type type_ptr =
   match name_opt_of_typedef_type_ptr type_ptr with
-  | Some name -> name = "instancetype"
+  | Some name -> String.equal name "instancetype"
   | None -> false
 
 let return_type_matches_class_type rtp type_decl_pointer =
@@ -452,7 +446,7 @@ let return_type_matches_class_type rtp type_decl_pointer =
     let return_type_decl_opt = type_ptr_to_objc_interface rtp in
     let return_type_decl_pointer_opt =
       Option.map ~f:if_decl_to_di_pointer_opt return_type_decl_opt in
-    (Some type_decl_pointer) = return_type_decl_pointer_opt
+    [%compare.equal : int option option] (Some type_decl_pointer) return_type_decl_pointer_opt
 
 let is_objc_factory_method if_decl meth_decl =
   let if_type_decl_pointer = if_decl_to_di_pointer_opt if_decl in

infer/src/clang/cAst_utils.mli

@@ -23,15 +23,9 @@ val name_opt_of_name_info_opt : Clang_ast_t.named_decl_info option -> string opt
 
 val property_name : Clang_ast_t.obj_c_property_impl_decl_info -> Clang_ast_t.named_decl_info
 
-val compare_property_attribute :
-  Clang_ast_t.property_attribute -> Clang_ast_t.property_attribute -> int
-
 val generated_ivar_name :
   Clang_ast_t.named_decl_info -> Clang_ast_t.named_decl_info
 
-val equal_property_attribute :
-  Clang_ast_t.property_attribute -> Clang_ast_t.property_attribute -> bool
-
 val get_memory_management_attributes : unit -> Clang_ast_t.property_attribute list
 
 val is_retain : Clang_ast_t.property_attribute option -> bool

infer/src/clang/cContext.ml

@@ -32,8 +32,7 @@ type curr_class =
   | ContextNoCls
 [@@deriving compare]
 
-let equal_curr_class curr_class1 curr_class2 =
+let equal_curr_class = [%compare.equal : curr_class]
-  compare_curr_class curr_class1 curr_class2 = 0
 
 type str_node_map = (string, Procdesc.Node.t) Hashtbl.t
 

infer/src/clang/cField_decl.ml

@@ -92,7 +92,7 @@ let modelled_fields_in_classes =
 
 let modelled_field class_name_info =
   let modelled_field_in_class res (class_name, field_name, typ) =
-    if class_name = class_name_info.Clang_ast_t.ni_name then
+    if String.equal class_name class_name_info.Clang_ast_t.ni_name then
       let class_name_qualified = class_name_info.Clang_ast_t.ni_qual_name in
       let field_name_qualified = CAst_utils.make_qual_name_decl class_name_qualified field_name in
       let name = CGeneral_utils.mk_class_field_name field_name_qualified in

infer/src/clang/cFrontend_config.ml

@@ -11,7 +11,9 @@ open! IStd
 
 (** Module that contains constants and global state used in the frontend *)
 
-type clang_lang = C | CPP | ObjC | ObjCPP
+type clang_lang = C | CPP | ObjC | ObjCPP [@@deriving compare]
+
+let equal_clang_lang = [%compare.equal : clang_lang]
 
 type translation_unit_context = {
   lang : clang_lang;

infer/src/clang/cFrontend_config.mli

@@ -11,7 +11,9 @@ open! IStd
 
 (** Module that contains constants and global state used in the frontend *)
 
-type clang_lang = C | CPP | ObjC | ObjCPP
+type clang_lang = C | CPP | ObjC | ObjCPP [@@deriving compare]
+
+val equal_clang_lang : clang_lang -> clang_lang -> bool
 
 type translation_unit_context = {
   lang : clang_lang;

infer/src/clang/cFrontend_errors.ml

@@ -135,7 +135,7 @@ let expand_checkers checkers =
     match acc with
     | True
     | False -> acc
-    | Atomic (name, [p]) when formula_id_const = p ->
+    | Atomic (name, [p]) when String.equal formula_id_const p ->
         Logging.out "  -Expanding formula identifier '%s'\n" name;
         (match Core.Std.String.Map.find map name with
          | Some f1 -> expand f1 map

infer/src/clang/cGeneral_utils.ml

@@ -44,7 +44,7 @@ let append_no_duplicates_methods list1 list2 =
   append_no_duplicates Procname.equal list1 list2
 
 let append_no_duplicates_annotations list1 list2 =
-  let eq (annot1, _) (annot2, _) = annot1.Annot.class_name = annot2.Annot.class_name in
+  let eq (annot1, _) (annot2, _) = String.equal annot1.Annot.class_name annot2.Annot.class_name in
   append_no_duplicates eq list1 list2
 
 let add_no_duplicates_fields field_tuple l =
@@ -86,7 +86,7 @@ let rec collect_list_tuples l (a, a1, b, c, d) =
 
 let is_static_var var_decl_info =
   match var_decl_info.Clang_ast_t.vdi_storage_class with
-  | Some sc -> sc = CFrontend_config.static
+  | Some sc -> String.equal sc CFrontend_config.static
   | _ -> false
 
 let block_procname_with_index defining_proc i =
@@ -139,11 +139,13 @@ let mk_class_field_name field_qual_name =
 
 let is_cpp_translation translation_unit_context =
   let lang = translation_unit_context.CFrontend_config.lang in
-  lang = CFrontend_config.CPP || lang = CFrontend_config.ObjCPP
+  CFrontend_config.equal_clang_lang lang CFrontend_config.CPP ||
+  CFrontend_config.equal_clang_lang lang CFrontend_config.ObjCPP
 
 let is_objc_extension translation_unit_context =
   let lang = translation_unit_context.CFrontend_config.lang in
-  lang = CFrontend_config.ObjC || lang = CFrontend_config.ObjCPP
+  CFrontend_config.equal_clang_lang lang CFrontend_config.ObjC ||
+  CFrontend_config.equal_clang_lang lang CFrontend_config.ObjCPP
 
 let rec get_mangled_method_name function_decl_info method_decl_info =
   (* For virtual methods return mangled name of the method from most base class
@@ -183,7 +185,7 @@ let mk_procname_from_function translation_unit_context name function_decl_info_o
     | Some m when is_cpp_translation translation_unit_context -> m
     | _ -> "" in
   let mangled = (Utils.string_crc_hex32 file) ^ mangled_name in
-  if String.length file = 0 && String.length mangled_name = 0 then
+  if String.is_empty file && String.is_empty mangled_name then
     Procname.from_string_c_fun name
   else
     Procname.C (Procname.c name mangled)

infer/src/clang/cLocation.ml

@@ -8,6 +8,7 @@
  *)
 
 open! IStd
+open! PVariant
 
 (** Module for function to retrieve the location (file, line, etc) of instructions *)
 

infer/src/clang/cMethod_signature.ml

@@ -66,13 +66,13 @@ let ms_get_return_param_typ { return_param_typ } =
 (* it has 1 argument (this includes self) *)
 let ms_is_getter { pointer_to_property_opt; args }  =
   Option.is_some pointer_to_property_opt &&
-  IList.length args = 1
+  Int.equal (IList.length args) 1
 
 (* A method is a setter if it has a link to a property and *)
 (* it has 2 argument (this includes self) *)
 let ms_is_setter { pointer_to_property_opt; args } =
   Option.is_some pointer_to_property_opt &&
-  IList.length args = 2
+  Int.equal (IList.length args) 2
 
 let make_ms name args ret_type attributes loc is_instance ?is_cpp_virtual language pointer_to_parent
     pointer_to_property_opt return_param_typ =

infer/src/clang/cMethod_trans.ml

@@ -23,7 +23,9 @@ exception Invalid_declaration
 type method_call_type =
   | MCVirtual
   | MCNoVirtual
-  | MCStatic
+  | MCStatic [@@deriving compare]
+
+let equal_method_call_type = [%compare.equal : method_call_type]
 
 type function_method_decl_info =
   | Func_decl_info of Clang_ast_t.function_decl_info * Clang_ast_t.type_ptr
@@ -297,10 +299,14 @@ let get_formal_parameters tenv ms =
     | [] -> []
     | (mangled, {Clang_ast_t.qt_type_ptr}):: pl' ->
         let should_add_pointer name ms =
-          let is_objc_self = name = CFrontend_config.self &&
+          let is_objc_self =
-                             CMethod_signature.ms_get_lang ms = CFrontend_config.ObjC in
+            String.equal name CFrontend_config.self &&
-          let is_cxx_this = name = CFrontend_config.this &&
+            CFrontend_config.equal_clang_lang
-                            CMethod_signature.ms_get_lang ms = CFrontend_config.CPP in
+              (CMethod_signature.ms_get_lang ms) CFrontend_config.ObjC in
+          let is_cxx_this =
+            String.equal name CFrontend_config.this &&
+            CFrontend_config.equal_clang_lang
+              (CMethod_signature.ms_get_lang ms) CFrontend_config.CPP in
           (is_objc_self && CMethod_signature.ms_is_instance ms) || is_cxx_this in
         let tp = if should_add_pointer (Mangled.to_string mangled) ms then
             (Ast_expressions.create_pointer_type qt_type_ptr)
@@ -377,14 +383,15 @@ let get_const_args_indices ~shift args =
 
 (** Creates a procedure description. *)
 let create_local_procdesc trans_unit_ctx cfg tenv ms fbody captured is_objc_inst_method =
-  let defined = not ((IList.length fbody) = 0) in
+  let defined = not (Int.equal (IList.length fbody) 0) in
   let proc_name = CMethod_signature.ms_get_name ms in
   let pname = Procname.to_string proc_name in
   let attributes = sil_func_attributes_of_attributes (CMethod_signature.ms_get_attributes ms) in
   let method_annotation =
     sil_method_annotation_of_args (CMethod_signature.ms_get_args ms) in
-  let is_cpp_inst_method = CMethod_signature.ms_is_instance ms
+  let is_cpp_inst_method =
-                           && CMethod_signature.ms_get_lang ms = CFrontend_config.CPP in
+    CMethod_signature.ms_is_instance ms &&
+    CFrontend_config.equal_clang_lang (CMethod_signature.ms_get_lang ms) CFrontend_config.CPP in
   let create_new_procdesc () =
     let formals = get_formal_parameters tenv ms in
     let captured_mangled = IList.map (fun (var, t) -> (Pvar.get_name var), t) captured in

infer/src/clang/cMethod_trans.mli

@@ -19,7 +19,9 @@ open! IStd
 type method_call_type =
   | MCVirtual
   | MCNoVirtual
-  | MCStatic
+  | MCStatic [@@deriving compare]
+
+val equal_method_call_type : method_call_type -> method_call_type -> bool
 
 val should_add_return_param : Typ.t -> is_objc_method:bool -> bool
 

infer/src/clang/cPredicates.ml

@@ -61,12 +61,12 @@ let pp_predicate fmt (name, arglist) =
   Format.fprintf fmt "%s(%a)" name (Pp.comma_seq Format.pp_print_string) arglist
 
 let is_declaration_kind decl s =
-  Clang_ast_proj.get_decl_kind_string decl = s
+  String.equal (Clang_ast_proj.get_decl_kind_string decl) s
 
 (* st |= call_method(m) *)
 let call_method m st =
   match st with
-  | Clang_ast_t.ObjCMessageExpr (_, _, _, omei) -> omei.omei_selector = m
+  | Clang_ast_t.ObjCMessageExpr (_, _, _, omei) -> String.equal omei.omei_selector m
   | _ -> false
 
 let property_name_contains_word word decl =
@@ -92,7 +92,7 @@ let decl_ref_is_in names st =
   | Clang_ast_t.DeclRefExpr (_, _, _, drti) ->
       (match drti.drti_decl_ref with
        | Some dr -> let ndi, _, _ = CAst_utils.get_info_from_decl_ref dr in
-           IList.exists (fun n -> n = ndi.ni_name) names
+           IList.exists (String.equal ndi.ni_name) names
        | _ -> false)
   | _ -> false
 
@@ -120,7 +120,7 @@ let is_property_pointer_type decl =
        | Some ObjCObjectPointerType _
        | Some BlockPointerType _ -> true
        | Some TypedefType (_, tti) ->
-           (CAst_utils.name_of_typedef_type_info tti) = CFrontend_config.id_cl
+           String.equal (CAst_utils.name_of_typedef_type_info tti) CFrontend_config.id_cl
        | exception Not_found -> false
        | _ -> false)
   | _ -> false
@@ -137,7 +137,7 @@ let is_ivar_atomic stmt =
       (match CAst_utils.get_decl ivar_pointer with
        | Some d ->
            let attributes = get_ivar_attributes d in
-           IList.exists (CAst_utils.equal_property_attribute `Atomic) attributes
+           IList.exists (PVariant.(=) `Atomic) attributes
        | _ -> false)
   | _ -> false
 
@@ -154,7 +154,7 @@ let is_method_property_accessor_of_ivar stmt context =
              match CAst_utils.get_decl_opt_with_decl_ref property_opt with
              | Some ObjCPropertyDecl (_, _, pdi) ->
                  (match pdi.opdi_ivar_decl with
-                  | Some decl_ref -> decl_ref.dr_decl_pointer = ivar_pointer
+                  | Some decl_ref -> Int.equal decl_ref.dr_decl_pointer ivar_pointer
                   | None -> false)
              | _ -> false
            else false
@@ -188,7 +188,7 @@ let is_binop_with_kind str_kind stmt =
     failwith ("Binary operator kind " ^ str_kind ^ " is not valid");
   match stmt with
   | Clang_ast_t.BinaryOperator (_, _, _, boi) ->
-      Clang_ast_proj.string_of_binop_kind boi.boi_kind = str_kind
+      String.equal (Clang_ast_proj.string_of_binop_kind boi.boi_kind) str_kind
   | _ -> false
 
 let is_unop_with_kind str_kind stmt =
@@ -196,18 +196,18 @@ let is_unop_with_kind str_kind stmt =
     failwith ("Unary operator kind " ^ str_kind ^ " is not valid");
   match stmt with
   | Clang_ast_t.UnaryOperator (_, _, _, uoi) ->
-      Clang_ast_proj.string_of_unop_kind uoi.uoi_kind = str_kind
+      String.equal (Clang_ast_proj.string_of_unop_kind uoi.uoi_kind) str_kind
   | _ -> false
 
 let is_stmt nodename stmt =
   if not (Clang_ast_proj.is_valid_astnode_kind nodename) then
     failwith ("Statement " ^ nodename ^ " is not a valid statement");
-  nodename = Clang_ast_proj.get_stmt_kind_string stmt
+  String.equal nodename (Clang_ast_proj.get_stmt_kind_string stmt)
 
 let is_decl nodename decl =
   if not (Clang_ast_proj.is_valid_astnode_kind nodename) then
     failwith ("Declaration " ^ nodename ^ " is not a valid declaration");
-  nodename = Clang_ast_proj.get_decl_kind_string decl
+  String.equal nodename (Clang_ast_proj.get_decl_kind_string decl)
 
 let isa classname stmt =
   match Clang_ast_proj.get_expr_tuple stmt with
@@ -220,5 +220,5 @@ let decl_unavailable_in_supported_ios_sdk decl =
   let available_attr_ios_sdk = get_available_attr_ios_sdk decl in
   match available_attr_ios_sdk, Config.iphoneos_target_sdk_version with
   | Some available_attr_ios_sdk, Some iphoneos_target_sdk_version ->
-      Utils.compare_versions available_attr_ios_sdk iphoneos_target_sdk_version = 1
+      Int.equal (Utils.compare_versions available_attr_ios_sdk iphoneos_target_sdk_version) 1
   | _ -> false

infer/src/clang/cTL.ml

@@ -53,6 +53,8 @@ type ast_node =
   | Stmt of Clang_ast_t.stmt
   | Decl of Clang_ast_t.decl
 
+let equal_ast_node = Poly.(=)
+
 module Debug = struct
   let pp_transition fmt trans_opt =
     let pp_aux fmt trans = match trans with
@@ -175,7 +177,7 @@ module Debug = struct
             let root_node = get_root tree in
             let children = get_children tree in
             let edge child_node =
-              if root_node.content.ast_node = child_node.content.ast_node then
+              if equal_ast_node root_node.content.ast_node child_node.content.ast_node then
                 Printf.sprintf "%d -> %d [style=dotted]" root_node.id child_node.id
               else
                 Printf.sprintf "%d -> %d [style=bold]" root_node.id child_node.id in
@@ -196,9 +198,9 @@ module Debug = struct
               let smart_string_of_formula phi =
                 let num_children = IList.length children in
                 match phi with
-                | And _ when num_children = 2 -> "(...) AND (...)"
+                | And _ when Int.equal num_children 2 -> "(...) AND (...)"
-                | Or _ when num_children = 2 -> "(...) OR (...)"
+                | Or _ when Int.equal num_children 2 -> "(...) OR (...)"
-                | Implies _ when num_children = 2 -> "(...) ==> (...)"
+                | Implies _ when Int.equal num_children 2 -> "(...) ==> (...)"
                 | Not _ -> "NOT(...)"
                 | _ -> Format.asprintf "%a" pp_formula phi in
               Format.sprintf "(%d)\\n%s\\n%s\\n%s"

infer/src/clang/cTrans.ml

@@ -8,6 +8,7 @@
  *)
 
 open! IStd
+open! PVariant
 
 (** Translates instructions: (statements and expressions) from the ast into sil *)
 
@@ -447,7 +448,7 @@ struct
         Some BuiltinDecl.__objc_release_cf
     | _ when CTrans_models.is_retain_builtin name type_ptr ->
         Some BuiltinDecl.__objc_retain_cf
-    | _ when name = CFrontend_config.malloc &&
+    | _ when String.equal name CFrontend_config.malloc &&
              CGeneral_utils.is_objc_extension trans_unit_ctx ->
         Some BuiltinDecl.malloc_no_fail
     | _ -> None
@@ -874,7 +875,7 @@ struct
             ~f:CTrans_models.is_cf_retain_release ~default:false callee_pname_opt in
         let act_params =
           let params = IList.tl (collect_exprs result_trans_subexprs) in
-          if IList.length params = IList.length params_stmt then
+          if Int.equal (IList.length params) (IList.length params_stmt) then
             params
           else (Logging.err_debug
                   "WARNING: stmt_list and res_trans_par.exps must have same size. \
@@ -913,7 +914,7 @@ struct
     let procname = Procdesc.get_proc_name context.procdesc in
     let sil_loc = CLocation.get_sil_location si context in
     (* first for method address, second for 'this' expression *)
-    assert ((IList.length result_trans_callee.exps) = 2);
+    assert (Int.equal (IList.length result_trans_callee.exps) 2);
     let (sil_method, _) = IList.hd result_trans_callee.exps in
     let callee_pname =
       match sil_method with
@@ -1012,12 +1013,13 @@ struct
     let receiver_kind = obj_c_message_expr_info.Clang_ast_t.omei_receiver_kind in
     let selector = obj_c_message_expr_info.Clang_ast_t.omei_selector in
     (* class method *)
-    if selector = CFrontend_config.class_method && CType.is_class method_type then
+    if String.equal selector CFrontend_config.class_method && CType.is_class method_type then
       let class_name = CMethod_trans.get_class_name_method_call_from_receiver_kind context
           obj_c_message_expr_info act_params in
       raise (Self.SelfClassException class_name)
       (* alloc or new *)
-    else if (selector = CFrontend_config.alloc) || (selector = CFrontend_config.new_str) then
+    else if String.equal selector CFrontend_config.alloc ||
+            String.equal selector CFrontend_config.new_str then
       match receiver_kind with
       | `Class type_ptr ->
           let class_opt =
@@ -1075,7 +1077,8 @@ struct
             obj_c_message_expr_info in
         let res_trans_subexpr_list = res_trans_add_self :: res_trans_subexpr_list in
         let subexpr_exprs = collect_exprs res_trans_subexpr_list in
-        let is_virtual = method_call_type = CMethod_trans.MCVirtual in
+        let is_virtual =
+          CMethod_trans.equal_method_call_type method_call_type CMethod_trans.MCVirtual in
         Cg.add_edge context.CContext.cg procname callee_name;
 
         let param_exps, instr_block_param =
@@ -1217,7 +1220,7 @@ struct
       IList.iter
         (fun n' -> Procdesc.node_set_succs_exn context.procdesc n' [prune_t; prune_f] [])
         res_trans_cond.leaf_nodes;
-      let rnodes = if (IList.length res_trans_cond.root_nodes) = 0 then
+      let rnodes = if Int.equal (IList.length res_trans_cond.root_nodes) 0 then
           [prune_t; prune_f]
         else res_trans_cond.root_nodes in
       { empty_res_trans with
@@ -1251,7 +1254,7 @@ struct
         (fun n -> Procdesc.node_set_succs_exn context.procdesc n res_trans_s2.root_nodes [])
         prune_to_s2;
       let root_nodes_to_parent =
-        if (IList.length res_trans_s1.root_nodes) = 0
+        if Int.equal (IList.length res_trans_s1.root_nodes) 0
         then res_trans_s1.leaf_nodes
         else res_trans_s1.root_nodes in
       let (exp1, typ1) = extract_exp res_trans_s1.exps in
@@ -1630,7 +1633,7 @@ struct
     let res_trans_subexpr_list =
       initListExpr_initializers_trans trans_state var_exp 0 stmts typ false stmt_info in
     let rh_exps = collect_exprs res_trans_subexpr_list in
-    if IList.length rh_exps = 0 then
+    if Int.equal (IList.length rh_exps) 0 then
       let exps =
         match Sil.zero_value_of_numerical_type_option var_type with
         | Some zero_exp -> [(zero_exp, typ)]
@@ -1644,7 +1647,7 @@ struct
           let i = IList.length lh - IList.length rh_exps in
           IList.drop_last i lh
         else lh in
-      if IList.length rh_exps = IList.length lh then
+      if Int.equal (IList.length rh_exps) (IList.length lh) then
         (* Creating new instructions by assigning right hand side to left hand side expressions *)
         let assign_instr (lh_exp, lh_t) (rh_exp, _) = Sil.Store (lh_exp, lh_t, rh_exp, sil_loc) in
         let assign_instrs =

infer/src/clang/cTrans_models.ml

@@ -12,10 +12,10 @@ open! IStd
 open Objc_models
 
 let is_cf_non_null_alloc pname =
-  Procname.to_string pname = CFrontend_config.cf_non_null_alloc
+  String.equal (Procname.to_string pname) CFrontend_config.cf_non_null_alloc
 
 let is_alloc pname =
-  Procname.to_string pname = CFrontend_config.cf_alloc
+  String.equal (Procname.to_string pname) CFrontend_config.cf_alloc
 
 let is_alloc_model typ pname =
   if Specs.summary_exists pname then false
@@ -27,13 +27,13 @@ let is_alloc_model typ pname =
     Core_foundation_model.is_core_lib_create typ funct
 
 let is_builtin_expect pname =
-  Procname.to_string pname = CFrontend_config.builtin_expect
+  String.equal (Procname.to_string pname) CFrontend_config.builtin_expect
 
 let is_builtin_object_size pname =
-  (Procname.to_string pname) = CFrontend_config.builtin_object_size
+  String.equal (Procname.to_string pname) CFrontend_config.builtin_object_size
 
 let is_replace_with_deref_first_arg pname =
-  (Procname.to_string pname) = CFrontend_config.replace_with_deref_first_arg_attr
+  String.equal (Procname.to_string pname) CFrontend_config.replace_with_deref_first_arg_attr
 
 let is_retain_predefined_model typ pname =
   let funct = Procname.to_string pname in
@@ -45,13 +45,13 @@ let is_release_predefined_model typ pname =
   Core_foundation_model.is_core_graphics_release typ funct
 
 let is_retain_method funct =
-  funct = CFrontend_config.retain
+  String.equal funct CFrontend_config.retain
 
 let is_release_method funct =
-  funct = CFrontend_config.release
+  String.equal funct CFrontend_config.release
 
 let is_autorelease_method funct =
-  funct = CFrontend_config.autorelease
+  String.equal funct CFrontend_config.autorelease
 
 let get_builtinname method_name =
   if is_retain_method method_name then
@@ -63,7 +63,7 @@ let get_builtinname method_name =
   else None
 
 let is_modeled_builtin funct =
-  funct = CFrontend_config.builtin_memset_chk
+  String.equal funct CFrontend_config.builtin_memset_chk
 
 let is_modeled_attribute attr_name =
   IList.mem String.equal attr_name CFrontend_config.modeled_function_attributes
@@ -89,17 +89,17 @@ let is_retain_builtin funct fun_type =
     | _ -> false
 
 let is_assert_log_s funct =
-  funct = CFrontend_config.assert_rtn ||
+  String.equal funct CFrontend_config.assert_rtn ||
-  funct = CFrontend_config.assert_fail ||
+  String.equal funct CFrontend_config.assert_fail ||
-  funct = CFrontend_config.fbAssertWithSignalAndLogFunctionHelper ||
+  String.equal funct CFrontend_config.fbAssertWithSignalAndLogFunctionHelper ||
   String.is_substring ~substring:CFrontend_config.google_MakeCheckOpString funct
 
 let is_assert_log_method m =
-  m = CFrontend_config.google_LogMessageFatal
+  String.equal m CFrontend_config.google_LogMessageFatal
 
 let is_handleFailureInMethod funct =
-  funct = CFrontend_config.handleFailureInMethod ||
+  String.equal funct CFrontend_config.handleFailureInMethod ||
-  funct = CFrontend_config.handleFailureInFunction
+  String.equal funct CFrontend_config.handleFailureInFunction
 
 let is_retain_or_release funct =
   is_retain_method funct ||
@@ -108,10 +108,10 @@ let is_retain_or_release funct =
 
 let is_toll_free_bridging pn =
   let funct = (Procname.to_string pn) in
-  funct = CFrontend_config.cf_bridging_release ||
+  String.equal funct CFrontend_config.cf_bridging_release ||
-  funct = CFrontend_config.cf_bridging_retain ||
+  String.equal funct CFrontend_config.cf_bridging_retain ||
-  funct = CFrontend_config.cf_autorelease ||
+  String.equal funct CFrontend_config.cf_autorelease ||
-  funct = CFrontend_config.ns_make_collectable
+  String.equal funct CFrontend_config.ns_make_collectable
 
 let is_cf_retain_release pn =
   Procname.equal pn BuiltinDecl.__objc_retain_cf
@@ -143,8 +143,8 @@ let get_predefined_ms_method condition class_name method_name method_kind mk_pro
 
 let get_predefined_ms_stringWithUTF8String class_name method_name mk_procname lang =
   let condition =
-    class_name = CFrontend_config.nsstring_cl
+    String.equal class_name CFrontend_config.nsstring_cl &&
-    && method_name = CFrontend_config.string_with_utf8_m in
+    String.equal method_name CFrontend_config.string_with_utf8_m in
   let id_type = Ast_expressions.create_id_type in
   let args = [(Mangled.from_string "x",
                Ast_expressions.create_char_star_qual_type ~is_const:true)] in
@@ -164,8 +164,8 @@ let get_predefined_ms_retain_release method_name mk_procname lang =
 
 let get_predefined_ms_autoreleasepool_init class_name method_name mk_procname lang =
   let condition =
-    method_name = CFrontend_config.init
+    String.equal method_name CFrontend_config.init &&
-    && class_name = CFrontend_config.nsautorelease_pool_cl in
+    String.equal class_name CFrontend_config.nsautorelease_pool_cl in
   let class_type = Ast_expressions.create_class_qual_type (class_name, `OBJC) in
   get_predefined_ms_method condition class_name method_name Procname.ObjCInstanceMethod
     mk_procname lang [(Mangled.from_string CFrontend_config.self, class_type)]
@@ -173,8 +173,10 @@ let get_predefined_ms_autoreleasepool_init class_name method_name mk_procname la
 
 let get_predefined_ms_nsautoreleasepool_release class_name method_name mk_procname lang =
   let condition =
-    (method_name = CFrontend_config.release || method_name = CFrontend_config.drain)
+    (String.equal method_name CFrontend_config.release ||
-    && class_name = CFrontend_config.nsautorelease_pool_cl in
+     String.equal method_name CFrontend_config.drain)
+    &&
+    String.equal class_name CFrontend_config.nsautorelease_pool_cl in
   let class_type = Ast_expressions.create_class_qual_type (class_name, `OBJC) in
   let args = [(Mangled.from_string CFrontend_config.self, class_type)] in
   get_predefined_ms_method condition class_name method_name Procname.ObjCInstanceMethod
@@ -182,7 +184,7 @@ let get_predefined_ms_nsautoreleasepool_release class_name method_name mk_procna
     [] (Some BuiltinDecl.__objc_release_autorelease_pool)
 
 let get_predefined_ms_is_kind_of_class class_name method_name mk_procname lang =
-  let condition = method_name = CFrontend_config.is_kind_of_class in
+  let condition = String.equal method_name CFrontend_config.is_kind_of_class in
   let class_type = Ast_expressions.create_class_qual_type (class_name, `OBJC) in
   let args = [(Mangled.from_string CFrontend_config.self, class_type)] in
   get_predefined_ms_method condition class_name method_name Procname.ObjCInstanceMethod
@@ -214,7 +216,8 @@ let is_dispatch_function_name function_name =
   let rec is_dispatch functions =
     match functions with
     | [] -> None
-    | (el, block_arg_pos):: rest -> if (el = function_name) then
+    | (el, block_arg_pos):: rest ->
-          Some (el, block_arg_pos)
+        if (String.equal el function_name)
+        then Some (el, block_arg_pos)
         else is_dispatch rest in
   is_dispatch dispatch_functions

infer/src/clang/cTrans_utils.ml

@@ -231,7 +231,7 @@ struct
 
   let own_priority_node pri stmt_info =
     match pri with
-    | Busy p when p = stmt_info.Clang_ast_t.si_pointer -> true
+    | Busy p when Int.equal p stmt_info.Clang_ast_t.si_pointer -> true
     | _ -> false
 
   (* Used by translation functions to handle potenatial cfg nodes. *)
@@ -356,9 +356,9 @@ let new_or_alloc_trans trans_state loc stmt_info type_ptr class_name_opt selecto
     match class_name_opt with
     | Some class_name -> class_name
     | None -> CType.classname_of_type function_type in
-  if selector = CFrontend_config.alloc then
+  if String.equal selector CFrontend_config.alloc then
     alloc_trans trans_state loc stmt_info function_type true None
-  else if selector = CFrontend_config.new_str then
+  else if String.equal selector CFrontend_config.new_str then
     objc_new_trans trans_state loc stmt_info class_name function_type
   else assert false
 
@@ -596,7 +596,7 @@ struct
     else empty_res_trans
 
   let is_var_self pvar is_objc_method =
-    let is_self = Mangled.to_string (Pvar.get_name pvar) = CFrontend_config.self in
+    let is_self = String.equal (Mangled.to_string (Pvar.get_name pvar)) CFrontend_config.self in
     is_self && is_objc_method
 
 end
@@ -612,7 +612,7 @@ let is_owning_name n =
     else (
       let prefix = Str.string_before s' (String.length fam) in
       let suffix = Str.string_after s' (String.length fam) in
-      prefix = fam && not (Str.string_match (Str.regexp "[a-z]") suffix 0)
+      String.equal prefix fam && not (Str.string_match (Str.regexp "[a-z]") suffix 0)
     ) in
   match Str.split (Str.regexp_string ":") n with
   | fst:: _ ->
@@ -706,7 +706,7 @@ let is_dispatch_function stmt_list =
   | _ -> None
 
 let is_block_enumerate_function mei =
-  mei.Clang_ast_t.omei_selector = CFrontend_config.enumerateObjectsUsingBlock
+  String.equal mei.Clang_ast_t.omei_selector CFrontend_config.enumerateObjectsUsingBlock
 
 (* This takes a variable of type struct or array and returns a list of expressions *)
 (* for each of its fields (also recursively, such that each field access is of a basic type) *)

infer/src/clang/cVar_decl.ml

@@ -8,6 +8,7 @@
  *)
 
 open! IStd
+open! PVariant
 
 (** Process variable declarations by saving them as local or global variables.  *)
 (** Computes the local variables of a function or method to be added to the procdesc *)
@@ -95,7 +96,8 @@ let captured_vars_from_block_info context cvl =
         (match dr.Clang_ast_t.dr_name, dr.Clang_ast_t.dr_type_ptr with
          | Some name_info, Some type_ptr ->
              let n = name_info.Clang_ast_t.ni_name in
-             if n = CFrontend_config.self && not (CContext.is_objc_instance context) then
+             if String.equal n CFrontend_config.self &&
+                not (CContext.is_objc_instance context) then
                vars
              else
                let pvar = sil_var_of_decl_ref context dr procname in

infer/src/eradicate/eradicate.ml

@@ -189,6 +189,8 @@ struct
     let module Initializers = struct
       type init = Procname.t * Procdesc.t
 
+      let equal_class_opt = [%compare.equal : string option]
+
       let final_typestates initializers_current_class =
         (* Get the private methods, from the same class, directly called by the initializers. *)
         let get_private_called (initializers : init list) : init list =
@@ -196,14 +198,14 @@ struct
           let do_proc (init_pn, init_pd) =
             let filter callee_pn callee_attributes =
               let is_private =
-                callee_attributes.ProcAttributes.access = PredSymb.Private in
+                PredSymb.equal_access callee_attributes.ProcAttributes.access PredSymb.Private in
               let same_class =
                 let get_class_opt pn = match pn with
                   | Procname.Java pn_java ->
                       Some (Procname.java_get_class_name pn_java)
                   | _ ->
                       None in
-                get_class_opt init_pn = get_class_opt callee_pn in
+                equal_class_opt (get_class_opt init_pn) (get_class_opt callee_pn) in
               is_private && same_class in
             let private_called = PatternMatch.proc_calls
                 Specs.proc_resolve_attributes init_pd filter in
@@ -280,7 +282,7 @@ struct
             pname_and_pdescs_with
               (function (pname, proc_attributes) ->
                  is_initializer proc_attributes &&
-                 get_class pname = get_class curr_pname) in
+                 equal_class_opt (get_class pname) (get_class curr_pname)) in
           final_typestates
             ((curr_pname, curr_pdesc) :: initializers_current_class)
         end
@@ -292,7 +294,7 @@ struct
             pname_and_pdescs_with
               (fun (pname, _) ->
                  Procname.is_constructor pname &&
-                 get_class pname = get_class curr_pname) in
+                 equal_class_opt (get_class pname) (get_class curr_pname)) in
           final_typestates constructors_current_class
         end
 

infer/src/eradicate/eradicateChecks.ml

@@ -56,14 +56,14 @@ let classify_procedure proc_attributes =
 
 
 let is_virtual = function
-  | (p, _, _):: _ when Mangled.to_string p = "this" -> true
+  | (p, _, _):: _ when String.equal (Mangled.to_string p) "this" -> true
   | _ -> false
 
 
 (** Check an access (read or write) to a field. *)
 let check_field_access tenv
     find_canonical_duplicate curr_pname node instr_ref exp fname ta loc : unit =
-  if TypeAnnotation.get_value Annotations.Nullable ta = true then
+  if TypeAnnotation.get_value Annotations.Nullable ta then
     let origin_descr = TypeAnnotation.descr_origin tenv ta in
     report_error tenv
       find_canonical_duplicate
@@ -82,7 +82,7 @@ let check_array_access tenv
     ta
     loc
     indexed =
-  if TypeAnnotation.get_value Annotations.Nullable ta = true then
+  if TypeAnnotation.get_value Annotations.Nullable ta then
     let origin_descr = TypeAnnotation.descr_origin tenv ta in
     report_error tenv
       find_canonical_duplicate
@@ -99,6 +99,9 @@ type from_call =
   | From_is_true_on_null (** returns true on null *)
   | From_optional_isPresent (** x.isPresent *)
   | From_containsKey (** x.containsKey *)
+[@@ deriving compare]
+
+let equal_from_call = [%compare.equal : from_call]
 
 (** Check the normalized "is zero" or "is not zero" condition of a prune instruction. *)
 let check_condition tenv case_zero find_canonical_duplicate curr_pdesc
@@ -141,13 +144,13 @@ let check_condition tenv case_zero find_canonical_duplicate curr_pdesc
   let is_temp = Idenv.exp_is_temp idenv e in
   let nonnull = is_fun_nonnull ta in
   let should_report =
-    TypeAnnotation.get_value Annotations.Nullable ta = false &&
+    not (TypeAnnotation.get_value Annotations.Nullable ta) &&
     (Config.eradicate_condition_redundant || nonnull) &&
     true_branch &&
     (not is_temp || nonnull) &&
     PatternMatch.type_is_class typ &&
     not (from_try_with_resources ()) &&
-    from_call = From_condition &&
+    equal_from_call from_call From_condition &&
     not (TypeAnnotation.origin_is_fun_library ta) in
   let is_always_true = not case_zero in
   let nonnull = is_fun_nonnull ta in
@@ -181,15 +184,15 @@ let check_field_assignment tenv
           Annotations.ia_is_field_injector_readwrite ia
       | _ ->
           false in
-    TypeAnnotation.get_value Annotations.Nullable ta_lhs = false &&
+    not (TypeAnnotation.get_value Annotations.Nullable ta_lhs) &&
-    TypeAnnotation.get_value Annotations.Nullable ta_rhs = true &&
+    TypeAnnotation.get_value Annotations.Nullable ta_rhs &&
     PatternMatch.type_is_class t_lhs &&
     not (Ident.java_fieldname_is_outer_instance fname) &&
     not (field_is_field_injector_readwrite ()) in
   let should_report_absent =
     Config.eradicate_optional_present &&
-    TypeAnnotation.get_value Annotations.Present ta_lhs = true &&
+    TypeAnnotation.get_value Annotations.Present ta_lhs &&
-    TypeAnnotation.get_value Annotations.Present ta_rhs = false &&
+    not (TypeAnnotation.get_value Annotations.Present ta_rhs) &&
     not (Ident.java_fieldname_is_outer_instance fname) in
   let should_report_mutable =
     let field_is_mutable () = match t_ia_opt with
@@ -278,7 +281,7 @@ let check_constructor_initialization tenv
                 final_type_annotation_with
                   true
                   (Lazy.force final_constructor_typestates)
-                  (fun ta -> TypeAnnotation.get_value Annotations.Nullable ta = true) in
+                  (fun ta -> TypeAnnotation.get_value Annotations.Nullable ta) in
 
               let should_check_field_initialization =
                 let in_current_class =
@@ -442,7 +445,7 @@ let check_call_parameters tenv
   let tot_param_num = IList.length sig_params - (if has_this then 1 else 0) in
   let rec check sparams cparams = match sparams, cparams with
     | (s1, ia1, t1) :: sparams', ((orig_e2, e2), t2) :: cparams' ->
-        let param_is_this = Mangled.to_string s1 = "this" in
+        let param_is_this = String.equal (Mangled.to_string s1) "this" in
         let formal_is_nullable = Annotations.ia_is_nullable ia1 in
         let formal_is_present = Annotations.ia_is_present ia1 in
         let (_, ta2, _) =
@@ -539,7 +542,7 @@ let check_overridden_annotations
     let current_params = annotated_signature.Annotations.params
     and overridden_params = overriden_signature.Annotations.params in
     let initial_pos = if is_virtual current_params then 0 else 1 in
-    if (IList.length current_params) = (IList.length overridden_params) then
+    if Int.equal (IList.length current_params) (IList.length overridden_params) then
       ignore (IList.fold_left2 compare initial_pos current_params overridden_params) in
 
   let check overriden_proc_name =

infer/src/eradicate/typeCheck.ml

@@ -385,7 +385,9 @@ let typecheck_instr
   let constructor_check_calls_this calls_this pn =
     match curr_pname, pn with
     | Procname.Java curr_pname_java, Procname.Java pn_java ->
-        if Procname.java_get_class_name curr_pname_java = Procname.java_get_class_name pn_java
+        if String.equal
+            (Procname.java_get_class_name curr_pname_java)
+            (Procname.java_get_class_name pn_java)
         then calls_this := true
     | _ ->
         () in
@@ -402,7 +404,7 @@ let typecheck_instr
             (* Drop reference parameters to this and outer objects. *)
             let is_hidden_parameter (n, _) =
               let n_str = Mangled.to_string n in
-              n_str = "this" ||
+              String.equal n_str "this" ||
               Str.string_match (Str.regexp "$bcvar[0-9]+") n_str 0 in
             let rec drop_n_args ntl = match ntl with
               | fp:: tail when is_hidden_parameter fp -> 1 + drop_n_args tail
@@ -573,7 +575,7 @@ let typecheck_instr
               IList.mapi
                 (fun i (_, typ) ->
                    let arg =
-                     if i = 0 &&
+                     if Int.equal i 0 &&
                         not (Procname.java_is_static callee_pname)
                      then "this"
                      else Printf.sprintf "arg%d" i in
@@ -634,7 +636,7 @@ let typecheck_instr
           | Some (t, ta, _) ->
               let should_report =
                 Config.eradicate_condition_redundant &&
-                TypeAnnotation.get_value Annotations.Nullable ta = false &&
+                not (TypeAnnotation.get_value Annotations.Nullable ta) &&
                 not (TypeAnnotation.origin_is_fun_library ta) in
               if checks.eradicate && should_report then
                 begin
@@ -824,7 +826,7 @@ let typecheck_instr
               else typestate1 in
             let has_method pn name = match pn with
               | Procname.Java pn_java ->
-                  Procname.java_get_method pn_java = name
+                  String.equal (Procname.java_get_method pn_java) name
               | _ ->
                   false in
             if Models.is_check_not_null callee_pname then
@@ -997,7 +999,7 @@ let typecheck_instr
             begin
               match from_call with
               | EradicateChecks.From_optional_isPresent ->
-                  if TypeAnnotation.get_value Annotations.Present ta = false
+                  if not (TypeAnnotation.get_value Annotations.Present ta)
                   then set_flag e' Annotations.Present true typestate2
                   else typestate2
               | EradicateChecks.From_is_true_on_null ->
@@ -1084,7 +1086,7 @@ let typecheck_node
           typestates_exn := typestate :: !typestates_exn
     | Sil.Store (Exp.Lvar pv, _, _, _) when
         Pvar.is_return pv &&
-        Procdesc.Node.get_kind node = Procdesc.Node.throw_kind ->
+        Procdesc.Node.equal_nodekind (Procdesc.Node.get_kind node) Procdesc.Node.throw_kind ->
         (* throw instruction *)
         typestates_exn := typestate :: !typestates_exn
     | _ -> () in
@@ -1107,7 +1109,9 @@ let typecheck_node
 
   let typestate_succ = IList.fold_left (do_instruction ext) typestate instrs in
   let dont_propagate =
-    Procdesc.Node.get_kind node = Procdesc.Node.exn_sink_kind (* don't propagate exceptions *)
+    Procdesc.Node.equal_nodekind
+      (Procdesc.Node.get_kind node)
+      Procdesc.Node.exn_sink_kind (* don't propagate exceptions *)
     ||
     !noreturn in
   if dont_propagate

infer/src/harness/androidFramework.ml

@@ -91,7 +91,7 @@ let get_lifecycle_for_framework_typ_opt tenv lifecycle_typ lifecycle_proc_strs =
         IList.find (fun decl_proc ->
             match decl_proc with
             | Procname.Java decl_proc_java ->
-                lifecycle_proc = Procname.java_get_method decl_proc_java
+                String.equal lifecycle_proc (Procname.java_get_method decl_proc_java)
             | _ ->
                 false
           ) methods in

infer/src/harness/inhabit.ml

@@ -61,7 +61,7 @@ let create_fresh_local_name () =
   "dummy_local" ^ string_of_int !local_name_cntr
 
 (** more forgiving variation of IList.tl that won't raise an exception on the empty list *)
-let tl_or_empty l = if l = [] then l else IList.tl l
+let tl_or_empty l = if List.is_empty l then l else IList.tl l
 
 let get_non_receiver_formals formals = tl_or_empty formals
 
@@ -173,7 +173,7 @@ and inhabit_constructor tenv constr_name (allocated_obj, obj_type) cfg env =
 let inhabit_call_with_args procname procdesc args env =
   let retval =
     let ret_typ = Procdesc.get_ret_type procdesc in
-    let is_void = ret_typ = Typ.Tvoid in
+    let is_void = Typ.equal ret_typ Typ.Tvoid in
     if is_void then None else Some (Ident.create_fresh Ident.knormal, ret_typ) in
   let call_instr =
     let fun_exp = fun_exp_from_name procname in

infer/src/integration/Maven.ml

@@ -56,7 +56,7 @@ let add_infer_profile_to_xml maven_xml infer_xml =
     | `El_start tag ->
         Xmlm.output xml_out elt_in;
         let tag_name = snd (fst tag) in
-        if tag_name = "profiles" then (
+        if String.equal tag_name "profiles" then (
           found_profiles_tag := true
         );
         process xml_in xml_out (tag_name::tag_stack)
@@ -86,7 +86,7 @@ let add_infer_profile_to_xml maven_xml infer_xml =
     | `Data data ->
         Xmlm.output xml_out elt_in;
         (match tag_stack with
-         | "id"::"profile"::"profiles"::_ when data = infer_profile_name ->
+         | "id"::"profile"::"profiles"::_ when String.equal data infer_profile_name ->
              L.do_out "Found infer profile, not adding one@.";
              found_infer_profile := true
          | "module"::"modules"::_ ->

infer/src/java/jFrontend.ml

@@ -9,6 +9,7 @@
  *)
 
 open! IStd
+open! PVariant
 
 open Javalib_pack
 open Sawja_pack
@@ -20,7 +21,7 @@ let add_edges
     (context : JContext.t) start_node exn_node exit_nodes method_body_nodes impl super_call =
   let pc_nb = Array.length method_body_nodes in
   let last_pc = pc_nb - 1 in
-  let is_last pc = (pc = last_pc) in
+  let is_last pc = Int.equal pc last_pc in
   let rec get_body_nodes pc =
     let current_nodes = method_body_nodes.(pc) in
     match current_nodes with
@@ -37,7 +38,7 @@ let add_edges
       match JContext.get_goto_jump context pc with
       | JContext.Next -> get_body_nodes (pc + 1)
       | JContext.Jump goto_pc ->
-          if pc = goto_pc then [] (* loop in goto *)
+          if Int.equal pc goto_pc then [] (* loop in goto *)
           else get_body_nodes goto_pc
       | JContext.Exit -> exit_nodes in
   let get_succ_nodes node pc =
@@ -105,8 +106,8 @@ let cache_classname cn =
   let splitted_root_dir =
     let rec split l p =
       match p with
-      | p when p = Filename.current_dir_name -> l
+      | p when String.equal p Filename.current_dir_name -> l
-      | p when p = Filename.dir_sep -> l
+      | p when String.equal p Filename.dir_sep -> l
       | p -> split ((Filename.basename p):: l) (Filename.dirname p) in
     split [] (Filename.dirname path) in
   let rec mkdir l p =
@@ -163,8 +164,8 @@ let should_capture classes package_opt source_basename node =
   let classname = Javalib.get_name node in
   let match_package pkg cn =
     match JTransType.package_to_string (JBasics.cn_package cn) with
-    | None -> pkg = ""
+    | None -> String.equal pkg ""
-    | Some found_pkg -> found_pkg = pkg in
+    | Some found_pkg -> String.equal found_pkg pkg in
   if JBasics.ClassSet.mem classname classes then
     begin
       match Javalib.get_sourcefile node with
@@ -172,10 +173,10 @@ let should_capture classes package_opt source_basename node =
       | Some found_basename ->
           begin
             match package_opt with
-            | None -> found_basename = source_basename
+            | None -> String.equal found_basename source_basename
             | Some pkg ->
                 match_package pkg classname
-                && found_basename = source_basename
+                && String.equal found_basename source_basename
           end
     end
   else false

infer/src/java/jTrans.ml

@@ -81,7 +81,7 @@ let get_undefined_method_call ovt =
               match ot with
               | JBasics.TArray _ -> assert false
               | JBasics.TClass cn ->
-                  if JBasics.cn_name cn = JConfig.string_cl then
+                  if String.equal (JBasics.cn_name cn) JConfig.string_cl then
                     "string_undefined"
                   else
                   if JBasics.cn_equal cn JBasics.java_lang_object then
@@ -97,7 +97,7 @@ let get_undefined_method_call ovt =
 let retrieve_fieldname fieldname =
   try
     let subs = Str.split (Str.regexp (Str.quote ".")) (Ident.fieldname_to_string fieldname) in
-    if IList.length subs = 0 then
+    if Int.equal (IList.length subs) 0 then
       assert false
     else
       IList.hd (IList.rev subs)
@@ -108,7 +108,7 @@ let get_field_name program static tenv cn fs =
   let { StructTyp.fields; statics; } = JTransType.get_class_struct_typ program tenv cn in
   match
     IList.find
-      (fun (fieldname, _, _) -> retrieve_fieldname fieldname = JBasics.fs_name fs)
+      (fun (fieldname, _, _) -> String.equal (retrieve_fieldname fieldname) (JBasics.fs_name fs))
       (if static then statics else fields)
   with
   | fieldname, _, _ ->
@@ -226,10 +226,10 @@ let get_test_operator op =
   | `Ne -> Binop.Ne
 
 let is_java_native cm =
-  (cm.Javalib.cm_implementation = Javalib.Native)
+  Poly.(=) cm.Javalib.cm_implementation Javalib.Native
 
 let is_clone ms =
-  JBasics.ms_name ms = JConfig.clone_name
+  String.equal (JBasics.ms_name ms) JConfig.clone_name
 
 let get_implementation cm =
   match cm.Javalib.cm_implementation with
@@ -258,7 +258,7 @@ let get_implementation cm =
       (hacked_bytecode, jbir_code)
 
 let update_constr_loc cn ms loc_start =
-  if (JBasics.ms_name ms) = JConfig.constructor_name then
+  if String.equal (JBasics.ms_name ms) JConfig.constructor_name then
     try ignore(JBasics.ClassMap.find cn !constr_loc_map)
     with Not_found -> constr_loc_map := (JBasics.ClassMap.add cn loc_start !constr_loc_map)
 
@@ -411,7 +411,7 @@ let rec expression (context : JContext.t) pc expr =
   | JBir.Const c ->
       begin
         match c with (* We use the constant <field> internally to mean a variable. *)
-        | `String s when (JBasics.jstr_pp s) = JConfig.field_cst ->
+        | `String s when String.equal (JBasics.jstr_pp s) JConfig.field_cst ->
             let varname = JConfig.field_st in
             let procname = (Procdesc.get_proc_name context.procdesc) in
             let pvar = Pvar.mk varname procname in
@@ -639,9 +639,9 @@ let detect_loop entry_pc impl =
       begin
         let visited_updated = Int.Set.add visited pc in
         match code.(pc) with
-        | JBir.Goto goto_pc when goto_pc = entry_pc -> (true, empty)
+        | JBir.Goto goto_pc when Int.equal goto_pc entry_pc -> (true, empty)
         | JBir.Goto goto_pc -> loop visited_updated goto_pc
-        | JBir.Ifd (_, if_pc) when if_pc = entry_pc -> (true, empty)
+        | JBir.Ifd (_, if_pc) when Int.equal if_pc entry_pc -> (true, empty)
         | JBir.Ifd (_, if_pc) ->
             let (loop_detected, visited_after) = loop visited_updated (pc + 1) in
             if loop_detected then
@@ -649,7 +649,7 @@ let detect_loop entry_pc impl =
             else
               loop visited_after if_pc
         | _ ->
-            if (pc + 1) = entry_pc then
+            if Int.equal (pc + 1) entry_pc then
               (true, empty)
             else
               loop visited_updated (pc + 1)
@@ -680,7 +680,7 @@ let is_this expr =
       begin
         match JBir.var_name_debug var with
         | None -> false
-        | Some name_opt -> Mangled.to_string JConfig.this = name_opt
+        | Some name_opt -> String.equal (Mangled.to_string JConfig.this) name_opt
       end
   | _ -> false
 

infer/src/java/jTransExn.ml

@@ -94,7 +94,7 @@ let translate_exceptions (context : JContext.t) exit_nodes get_body_nodes handle
           create_node loc node_kind_false instrs_false in
         Procdesc.node_set_succs_exn procdesc node_true catch_nodes exit_nodes;
         Procdesc.node_set_succs_exn procdesc node_false succ_nodes exit_nodes;
-        let is_finally = handler.JBir.e_catch_type = None in
+        let is_finally = is_none handler.JBir.e_catch_type in
         if is_finally
         then [node_true] (* TODO (#4759480): clean up the translation so prune nodes are not created at all *)
         else [node_true; node_false] in

infer/src/java/jTransType.ml

@@ -173,7 +173,7 @@ let method_signature_names ms =
   let return_type_name =
     match JBasics.ms_rtype ms with
     | None ->
-        if JBasics.ms_name ms = JConfig.constructor_name then
+        if String.equal (JBasics.ms_name ms) JConfig.constructor_name then
           None
         else
           Some (None, JConfig.void)
@@ -384,7 +384,7 @@ let sizeof_of_object_type program tenv ot subtypes =
 
 (** return the name and type of a formal parameter, looking up the class name in case of "this" *)
 let param_type program tenv cn name vt =
-  if (JBir.var_name_g name) = Mangled.to_string JConfig.this
+  if String.equal (JBir.var_name_g name) (Mangled.to_string JConfig.this)
   then get_class_type program tenv cn
   else value_type program tenv vt
 

infer/src/unit/TraceTests.ml

@@ -58,7 +58,7 @@ module MockSource = struct
        let get_tainted_formals _ = assert false
      end))
 
-  let equal source1 source2 = compare source1 source2 = 0
+  let equal = [%compare.equal : t]
 end
 
 module MockSink = struct
@@ -67,7 +67,7 @@ module MockSink = struct
 
   let get _ = assert false
 
-  let equal sink1 sink2 = compare sink1 sink2 = 0
+  let equal = [%compare.equal : t]
 end
 
 
@@ -76,7 +76,7 @@ module MockTrace = Trace.Make(struct
     module Sink = MockSink
 
     let should_report source sink =
-      Source.kind source = Sink.kind sink
+      [%compare.equal : MockTraceElem.t] (Source.kind source) (Sink.kind sink)
   end)
 
 let tests =

infer/src/unit/accessPathTests.ml

@@ -140,7 +140,7 @@ let tests =
         F.fprintf fmt "Expected %s but got %s" expected actual in
       let assert_eq input_aps expected =
         let input = F.asprintf "%a" AccessPathDomains.Set.pp input_aps in
-        assert_equal ~cmp:(=) ~pp_diff input expected in
+        assert_equal ~cmp:String.equal ~pp_diff input expected in
       let aps1 = AccessPathDomains.Set.of_list [x_exact; x_abstract] in (* { x*, x } *)
       let aps2 = AccessPathDomains.Set.add xF_exact aps1 in (* x*, x, x.f *)
       let aps3 = AccessPathDomains.Set.add yF_exact aps2 in (* x*, x, x.f, y.f *)

infer/src/unit/accessTreeTests.ml

@@ -445,7 +445,7 @@ let tests =
           (fun (ap, trace) -> AccessPath.equal ap ap_in && MockTraceDomain.equal trace trace_in)
           ap_traces in
 
-      assert_bool "Should have six ap/trace pairs" (IList.length ap_traces = 6);
+      assert_bool "Should have six ap/trace pairs" (Int.equal (IList.length ap_traces) 6);
       assert_bool "has x pair" (has_ap_trace_pair x x_trace);
       assert_bool "has xF pair" (has_ap_trace_pair xF xF_trace);
       assert_bool "has xFG pair" (has_ap_trace_pair xFG xFG_trace);

infer/src/unit/procCfgTests.ml

@@ -96,7 +96,9 @@ let tests =
       end;
       assert_bool
         "underlying_node should return node of underlying CFG type"
-        (Procdesc.Node.get_id (BackwardInstrCfg.underlying_node n1) = BackwardCfg.id n1) in
+        (Procdesc.Node.equal_id
+           (Procdesc.Node.get_id (BackwardInstrCfg.underlying_node n1))
+           (BackwardCfg.id n1)) in
     "instr_test">::instr_test_ in
 
   let graph_tests = [

infer/src/unit/schedulerTests.ml

@@ -35,13 +35,13 @@ module MockProcCfg = struct
   include (MockNode : module type of MockNode with type t := node)
   type t = (node * node list) list
 
-  let compare_id = Int.compare
+  let equal_id = Int.equal
 
   let succs t n =
     try
       let node_id = id n in
       IList.find
-        (fun (node, _) -> compare_id (id node) node_id = 0)
+        (fun (node, _) -> equal_id (id node) node_id)
         t
       |> snd
     with Not_found -> []
@@ -51,7 +51,7 @@ module MockProcCfg = struct
       let node_id = id n in
       IList.filter
         (fun (_, succs) ->
-           IList.exists (fun node -> compare_id (id node) node_id = 0) succs)
+           IList.exists (fun node -> equal_id (id node) node_id) succs)
         t
       |> IList.map fst
     with Not_found -> []