diff --git a/infer/src/IR/Const.re b/infer/src/IR/Const.re
index 8fde16d39..2c5866463 100644
--- a/infer/src/IR/Const.re
+++ b/infer/src/IR/Const.re
@@ -40,11 +40,11 @@ let compare (c1: t) (c2: t) :int =>
   | (Cfloat f1, Cfloat f2) => float_compare f1 f2
   | (Cfloat _, _) => (-1)
   | (_, Cfloat _) => 1
-  | (Cclass c1, Cclass c2) => Ident.name_compare c1 c2
+  | (Cclass c1, Cclass c2) => Ident.compare_name c1 c2
   | (Cclass _, _) => (-1)
   | (_, Cclass _) => 1
   | (Cptr_to_fld fn1 t1, Cptr_to_fld fn2 t2) =>
-    let n = Ident.fieldname_compare fn1 fn2;
+    let n = Ident.compare_fieldname fn1 fn2;
     if (n != 0) {
       n
     } else {
diff --git a/infer/src/IR/Exp.re b/infer/src/IR/Exp.re
index ef5f42748..284053ff8 100644
--- a/infer/src/IR/Exp.re
+++ b/infer/src/IR/Exp.re
@@ -133,7 +133,7 @@ let rec compare e1 e2 =>
     if (n != 0) {
       n
     } else {
-      let n = Ident.fieldname_compare f1 f2;
+      let n = Ident.compare_fieldname f1 f2;
       if (n != 0) {
         n
       } else {
diff --git a/infer/src/IR/Ident.re b/infer/src/IR/Ident.re
index c87826fed..f11bbee36 100644
--- a/infer/src/IR/Ident.re
+++ b/infer/src/IR/Ident.re
@@ -18,119 +18,72 @@ let module L = Logging;
 
 let module F = Format;
 
-type name = string;
+type name = string [@@deriving compare];
 
-type fieldname = {fpos: int, fname: Mangled.t};
+let equal_name x y => 0 == compare_name x y;
 
-type kind = int;
+type fieldname = {fpos: int, fname: Mangled.t} [@@deriving compare];
 
-let kprimed = (-1);
+let equal_fieldname x y => 0 == compare_fieldname x y;
 
-let knormal = 0;
+type kind =
+  | KNone
+  /** special kind of "null ident" (basically, a more compact way of implementing an ident option).
+      useful for situations when an instruction requires an id, but no one should read the result. */
+  | KFootprint
+  | KNormal
+  | KPrimed
+[@@deriving compare];
 
-let kfootprint = 1;
+let kfootprint = KFootprint;
 
+let knormal = KNormal;
 
-/** special kind of "null ident" (basically, a more compact way of implementing an ident option).
-    useful for situations when an instruction requires an id, but no one should read the result. */
-let knone = 2;
+let kprimed = KPrimed;
+
+let equal_kind x y => 0 == compare_kind x y;
 
 /* timestamp for a path identifier */
 let path_ident_stamp = (-3);
 
-type t = {kind: int, name: name, stamp: int};
-
-type _ident = t;
-
-
-/** {2 Comparison Functions} */
-let name_compare = string_compare;
-
-let fieldname_compare fn1 fn2 => {
-  let n = int_compare fn1.fpos fn2.fpos;
-  if (n != 0) {
-    n
-  } else {
-    Mangled.compare fn1.fname fn2.fname
-  }
-};
+type t = {kind: kind, name: name, stamp: int} [@@deriving compare];
 
-let name_equal = string_equal;
-
-let kind_equal k1 k2 => k1 === k2;
-
-let compare i1 i2 => {
-  let n = i2.kind - i1.kind;
-  if (n != 0) {
-    n
-  } else {
-    let n = name_compare i1.name i2.name;
-    if (n != 0) {
-      n
-    } else {
-      int_compare i1.stamp i2.stamp
-    }
-  }
-};
-
-let equal i1 i2 =>
-  i1.stamp === i2.stamp &&
-  i1.kind === i2.kind && name_equal i1.name i2.name /* most unlikely first */;
-
-let fieldname_equal fn1 fn2 => fieldname_compare fn1 fn2 == 0;
-
-let rec ident_list_compare il1 il2 =>
-  switch (il1, il2) {
-  | ([], []) => 0
-  | ([], _) => (-1)
-  | (_, []) => 1
-  | ([i1, ...l1], [i2, ...l2]) =>
-    let n = compare i1 i2;
-    if (n != 0) {
-      n
-    } else {
-      ident_list_compare l1 l2
-    }
-  };
-
-let ident_list_equal ids1 ids2 => ident_list_compare ids1 ids2 == 0;
+/* most unlikely first */
+let equal i1 i2 => i1.stamp === i2.stamp && i1.kind === i2.kind && equal_name i1.name i2.name;
 
 
 /** {2 Set for identifiers} */
 let module IdentSet = Set.Make {
-  type t = _ident;
+  type nonrec t = t;
   let compare = compare;
 };
 
 let module IdentMap = Map.Make {
-  type t = _ident;
+  type nonrec t = t;
   let compare = compare;
 };
 
 let module IdentHash = Hashtbl.Make {
-  type t = _ident;
+  type nonrec t = t;
   let equal = equal;
   let hash (id: t) => Hashtbl.hash id;
 };
 
 let module FieldSet = Set.Make {
-  type t = fieldname;
-  let compare = fieldname_compare;
+  type t = fieldname [@@deriving compare];
 };
 
 let module FieldMap = Map.Make {
-  type t = fieldname;
-  let compare = fieldname_compare;
+  type t = fieldname [@@deriving compare];
 };
 
 let idlist_to_idset ids => IList.fold_left (fun set id => IdentSet.add id set) IdentSet.empty ids;
 
 
 /** {2 Conversion between Names and Strings} */
-
 let module NameHash = Hashtbl.Make {
   type t = name;
-  let equal = name_equal;
+  let equal = equal_name;
   let hash = Hashtbl.hash;
 };
 
@@ -215,7 +168,7 @@ let fieldname_hidden = create_fieldname (Mangled.from_string ".hidden") 0;
 
 
 /** hidded fieldname constant */
-let fieldname_is_hidden fn => fieldname_equal fn fieldname_hidden;
+let fieldname_is_hidden fn => equal_fieldname fn fieldname_hidden;
 
 
 /** {2 Functions and Hash Tables for Managing Stamps} */
@@ -288,9 +241,9 @@ let name_return = Mangled.from_string "return";
 
 /** Return the standard name for the given kind */
 let standard_name kind =>
-  if (kind === knormal || kind === knone) {
+  if (kind === KNormal || kind === KNone) {
     name_normal
-  } else if (kind === kfootprint) {
+  } else if (kind === KFootprint) {
     name_footprint
   } else {
     name_primed
@@ -309,21 +262,21 @@ let create kind stamp => create_with_stamp kind (standard_name kind) stamp;
 
 
 /** Generate a normal identifier with the given name and stamp */
-let create_normal name stamp => create_with_stamp knormal name stamp;
+let create_normal name stamp => create_with_stamp KNormal name stamp;
 
 
 /** Create a fresh identifier with default name for the given kind. */
 let create_fresh kind => NameGenerator.create_fresh_ident kind (standard_name kind);
 
-let create_none () => create_fresh knone;
+let create_none () => create_fresh KNone;
 
 
 /** Generate a primed identifier with the given name and stamp */
-let create_primed name stamp => create_with_stamp kprimed name stamp;
+let create_primed name stamp => create_with_stamp KPrimed name stamp;
 
 
 /** Generate a footprint identifier with the given name and stamp */
-let create_footprint name stamp => create_with_stamp kfootprint name stamp;
+let create_footprint name stamp => create_with_stamp KFootprint name stamp;
 
 
 /** {2 Functions for Identifiers} */
@@ -331,23 +284,23 @@ let create_footprint name stamp => create_with_stamp kfootprint name stamp;
 /** Get a name of an identifier */
 let get_name id => id.name;
 
-let is_primed (id: t) => id.kind === kprimed;
+let is_primed (id: t) => id.kind === KPrimed;
 
-let is_normal (id: t) => id.kind === knormal || id.kind === knone;
+let is_normal (id: t) => id.kind === KNormal || id.kind === KNone;
 
-let is_footprint (id: t) => id.kind === kfootprint;
+let is_footprint (id: t) => id.kind === KFootprint;
 
-let is_none (id: t) => id.kind == knone;
+let is_none (id: t) => id.kind == KNone;
 
-let is_path (id: t) => id.kind === knormal && id.stamp == path_ident_stamp;
+let is_path (id: t) => id.kind === KNormal && id.stamp == path_ident_stamp;
 
 let make_unprimed id =>
-  if (id.kind != kprimed) {
+  if (id.kind != KPrimed) {
     assert false
-  } else if (id.kind === knone) {
-    {...id, kind: knone}
+  } else if (id.kind === KNone) {
+    {...id, kind: KNone}
   } else {
-    {...id, kind: knormal}
+    {...id, kind: KNormal}
   };
 
 
@@ -367,14 +320,14 @@ let create_path pathstring =>
 
 /** Convert an identifier to a string. */
 let to_string id =>
-  if (id.kind === knone) {
+  if (id.kind === KNone) {
     "_"
   } else {
     let base_name = name_to_string id.name;
     let prefix =
-      if (id.kind === kfootprint) {
+      if (id.kind === KFootprint) {
         "@"
-      } else if (id.kind === knormal) {
+      } else if (id.kind === KNormal) {
         ""
       } else {
         "_"
@@ -406,9 +359,9 @@ let pp pe f id =>
   | PP_LATEX =>
     let base_name = name_to_string id.name;
     let style =
-      if (id.kind == kfootprint) {
+      if (id.kind == KFootprint) {
         Latex.Boldface
-      } else if (id.kind == knormal) {
+      } else if (id.kind == KNormal) {
         Latex.Roman
       } else {
         Latex.Roman
diff --git a/infer/src/IR/Ident.rei b/infer/src/IR/Ident.rei
index 4e2ebfa70..522b2ef95 100644
--- a/infer/src/IR/Ident.rei
+++ b/infer/src/IR/Ident.rei
@@ -16,19 +16,35 @@ open! Utils;
 /** Identifiers: program variables and logical variables */
 
 /** Program and logical variables. */
-type t;
+type t [@@deriving compare];
+
+
+/** Equality for identifiers. */
+let equal: t => t => bool;
 
 
 /** Names used to replace strings. */
-type name;
+type name [@@deriving compare];
+
+
+/** Equality for names. */
+let equal_name: name => name => bool;
 
 
 /** Names for fields of class/struct/union */
-type fieldname;
+type fieldname [@@deriving compare];
+
+
+/** Equality for field names. */
+let equal_fieldname: fieldname => fieldname => bool;
 
 
 /** Kind of identifiers. */
-type kind;
+type kind [@@deriving compare];
+
+
+/** Equality for kind. */
+let equal_kind: kind => kind => bool;
 
 
 /** Set for identifiers. */
@@ -210,44 +226,6 @@ let get_stamp: t => int;
 let set_stamp: t => int => t;
 
 
-/** {2 Comparision Functions} */
-
-/** Comparison for names. */
-let name_compare: name => name => int;
-
-
-/** Comparison for field names. */
-let fieldname_compare: fieldname => fieldname => int;
-
-
-/** Equality for names. */
-let name_equal: name => name => bool;
-
-
-/** Equality for field names. */
-let fieldname_equal: fieldname => fieldname => bool;
-
-
-/** Equality for kind. */
-let kind_equal: kind => kind => bool;
-
-
-/** Comparison for identifiers. */
-let compare: t => t => int;
-
-
-/** Equality for identifiers. */
-let equal: t => t => bool;
-
-
-/** Comparison for lists of identities */
-let ident_list_compare: list t => list t => int;
-
-
-/** Equality for lists of identities */
-let ident_list_equal: list t => list t => bool;
-
-
 /** {2 Pretty Printing} */
 
 /** Pretty print a name. */
diff --git a/infer/src/IR/Sil.re b/infer/src/IR/Sil.re
index 6fcc062c0..91df934cb 100644
--- a/infer/src/IR/Sil.re
+++ b/infer/src/IR/Sil.re
@@ -408,7 +408,7 @@ let rec strexp_compare inst::inst=false se1 se2 =>
       }
     }
   }
-and fld_strexp_compare fse1 fse2 => pair_compare Ident.fieldname_compare strexp_compare fse1 fse2
+and fld_strexp_compare fse1 fse2 => pair_compare Ident.compare_fieldname strexp_compare fse1 fse2
 and fld_strexp_list_compare fsel1 fsel2 => IList.compare fld_strexp_compare fsel1 fsel2
 and exp_strexp_compare ese1 ese2 => pair_compare Exp.compare strexp_compare ese1 ese2
 and exp_strexp_list_compare esel1 esel2 => IList.compare exp_strexp_compare esel1 esel2;
@@ -508,11 +508,11 @@ and hpara_compare hp1 hp2 => {
     if (n != 0) {
       n
     } else {
-      let n = Ident.ident_list_compare hp1.svars hp2.svars;
+      let n = IList.compare Ident.compare hp1.svars hp2.svars;
       if (n != 0) {
         n
       } else {
-        let n = Ident.ident_list_compare hp1.evars hp2.evars;
+        let n = IList.compare Ident.compare hp1.evars hp2.evars;
         if (n != 0) {
           n
         } else {
@@ -535,11 +535,11 @@ and hpara_dll_compare hp1 hp2 => {
       if (n != 0) {
         n
       } else {
-        let n = Ident.ident_list_compare hp1.svars_dll hp2.svars_dll;
+        let n = IList.compare Ident.compare hp1.svars_dll hp2.svars_dll;
         if (n != 0) {
           n
         } else {
-          let n = Ident.ident_list_compare hp1.evars_dll hp2.evars_dll;
+          let n = IList.compare Ident.compare hp1.evars_dll hp2.evars_dll;
           if (n != 0) {
             n
           } else {
@@ -2479,7 +2479,7 @@ let rec exp_compare_structural e1 e2 exp_map => {
       if (n != 0) {
         n
       } else {
-        let n = Ident.fieldname_compare f1 f2;
+        let n = Ident.compare_fieldname f1 f2;
         if (n != 0) {
           n
         } else {
diff --git a/infer/src/IR/StructTyp.re b/infer/src/IR/StructTyp.re
index 9a205208b..d06580857 100644
--- a/infer/src/IR/StructTyp.re
+++ b/infer/src/IR/StructTyp.re
@@ -33,7 +33,7 @@ type t = {
 type lookup = Typename.t => option t;
 
 let fld_typ_ann_compare fta1 fta2 =>
-  triple_compare Ident.fieldname_compare Typ.compare Annot.Item.compare fta1 fta2;
+  triple_compare Ident.compare_fieldname Typ.compare Annot.Item.compare fta1 fta2;
 
 let pp pe pp_base name f {fields} =>
   if false {
@@ -107,7 +107,7 @@ let fld_typ lookup::lookup default::default fn (typ: Typ.t) =>
   | Tstruct name =>
     switch (lookup name) {
     | Some {fields} =>
-      try (snd3 (IList.find (fun (f, _, _) => Ident.fieldname_equal f fn) fields)) {
+      try (snd3 (IList.find (fun (f, _, _) => Ident.equal_fieldname f fn) fields)) {
       | Not_found => default
       }
     | None => default
@@ -123,7 +123,7 @@ let get_field_type_and_annotation lookup::lookup fn (typ: Typ.t) =>
     | Some {fields, statics} =>
       try {
         let (_, t, a) =
-          IList.find (fun (f, _, _) => Ident.fieldname_equal f fn) (fields @ statics);
+          IList.find (fun (f, _, _) => Ident.equal_fieldname f fn) (fields @ statics);
         Some (t, a)
       } {
       | Not_found => None
diff --git a/infer/src/backend/abs.ml b/infer/src/backend/abs.ml
index e2d23aceb..982e8f7bf 100644
--- a/infer/src/backend/abs.ml
+++ b/infer/src/backend/abs.ml
@@ -469,7 +469,7 @@ let discover_para_candidates tenv p =
   let edges = ref [] in
   let add_edge edg = edges := edg :: !edges in
   let get_edges_strexp rec_flds root se =
-    let is_rec_fld fld = IList.exists (Ident.fieldname_equal fld) rec_flds in
+    let is_rec_fld fld = IList.exists (Ident.equal_fieldname fld) rec_flds in
     match se with
     | Sil.Eexp _ | Sil.Earray _ -> ()
     | Sil.Estruct (fsel, _) ->
@@ -505,7 +505,7 @@ let discover_para_dll_candidates tenv p =
   let edges = ref [] in
   let add_edge edg = (edges := edg :: !edges) in
   let get_edges_strexp rec_flds root se =
-    let is_rec_fld fld = IList.exists (Ident.fieldname_equal fld) rec_flds in
+    let is_rec_fld fld = IList.exists (Ident.equal_fieldname fld) rec_flds in
     match se with
     | Sil.Eexp _ | Sil.Earray _ -> ()
     | Sil.Estruct (fsel, _) ->
@@ -1004,7 +1004,7 @@ let cycle_has_weak_or_unretained_or_assign_field tenv cycle =
   let get_item_annotation (t: Typ.t) fn =
     match t with
     | Tstruct name -> (
-        let equal_fn (fn', _, _) = Ident.fieldname_equal fn fn' in
+        let equal_fn (fn', _, _) = Ident.equal_fieldname fn fn' in
         match Tenv.lookup tenv name with
         | Some { fields; statics } -> (
             try trd3 (IList.find equal_fn (fields @ statics))
diff --git a/infer/src/backend/absarray.ml b/infer/src/backend/absarray.ml
index bf335957e..a22afd4c8 100644
--- a/infer/src/backend/absarray.ml
+++ b/infer/src/backend/absarray.ml
@@ -76,8 +76,8 @@ end = struct
     | Sil.Estruct (fsel, _), Tstruct name, Field (fld, _) :: syn_offs' -> (
         match Tenv.lookup tenv name with
         | Some { fields } ->
-            let se' = snd (IList.find (fun (f', _) -> Ident.fieldname_equal f' fld) fsel) in
-            let t' = snd3 (IList.find (fun (f', _, _) -> Ident.fieldname_equal f' fld) fields) in
+            let se' = snd (IList.find (fun (f', _) -> Ident.equal_fieldname f' fld) fsel) in
+            let t' = snd3 (IList.find (fun (f', _, _) -> Ident.equal_fieldname f' fld) fields) in
             get_strexp_at_syn_offsets tenv se' t' syn_offs'
         | None ->
             fail ()
@@ -96,14 +96,14 @@ end = struct
     | Sil.Estruct (fsel, inst), Tstruct name, Field (fld, _) :: syn_offs' -> (
         match Tenv.lookup tenv name with
         | Some { fields } ->
-            let se' = snd (IList.find (fun (f', _) -> Ident.fieldname_equal f' fld) fsel) in
+            let se' = snd (IList.find (fun (f', _) -> Ident.equal_fieldname f' fld) fsel) in
             let t' = (fun (_,y,_) -> y)
                 (IList.find (fun (f', _, _) ->
-                     Ident.fieldname_equal f' fld) fields) in
+                     Ident.equal_fieldname f' fld) fields) in
             let se_mod = replace_strexp_at_syn_offsets tenv se' t' syn_offs' update in
             let fsel' =
               IList.map (fun (f'', se'') ->
-                  if Ident.fieldname_equal f'' fld then (fld, se_mod) else (f'', se'')
+                  if Ident.equal_fieldname f'' fld then (fld, se_mod) else (f'', se'')
                 ) fsel in
             Sil.Estruct (fsel', inst)
         | None ->
@@ -178,7 +178,7 @@ end = struct
       | (f, se) :: fsel' ->
           begin
             try
-              let t = snd3 (IList.find (fun (f', _, _) -> Ident.fieldname_equal f' f) ftal) in
+              let t = snd3 (IList.find (fun (f', _, _) -> Ident.equal_fieldname f' f) ftal) in
               find_offset_sexp sigma_other hpred root ((Field (f, typ)) :: offs) se t
             with Not_found ->
               L.d_strln ("Can't find field " ^ (Ident.fieldname_to_string f) ^ " in StrexpMatch.find")
diff --git a/infer/src/backend/dom.ml b/infer/src/backend/dom.ml
index f23ca4083..6a6813945 100644
--- a/infer/src/backend/dom.ml
+++ b/infer/src/backend/dom.ml
@@ -961,7 +961,7 @@ let rec exp_partial_join (e1: Exp.t) (e2: Exp.t) : Exp.t =
       if not (Pvar.equal pvar1 pvar2) then (L.d_strln "failure reason 25"; raise IList.Fail)
       else e1
   | Exp.Lfield(e1, f1, t1), Exp.Lfield(e2, f2, _) ->
-      if not (Ident.fieldname_equal f1 f2) then (L.d_strln "failure reason 26"; raise IList.Fail)
+      if not (Ident.equal_fieldname f1 f2) then (L.d_strln "failure reason 26"; raise IList.Fail)
       else Exp.Lfield(exp_partial_join e1 e2, f1, t1) (* should be t1 = t2 *)
   | Exp.Lindex(e1, e1'), Exp.Lindex(e2, e2') ->
       let e1'' = exp_partial_join e1 e2 in
@@ -1044,7 +1044,7 @@ let rec exp_partial_meet (e1: Exp.t) (e2: Exp.t) : Exp.t =
       if not (Pvar.equal pvar1 pvar2) then (L.d_strln "failure reason 35"; raise IList.Fail)
       else e1
   | Exp.Lfield(e1, f1, t1), Exp.Lfield(e2, f2, _) ->
-      if not (Ident.fieldname_equal f1 f2) then (L.d_strln "failure reason 36"; raise IList.Fail)
+      if not (Ident.equal_fieldname f1 f2) then (L.d_strln "failure reason 36"; raise IList.Fail)
       else Exp.Lfield(exp_partial_meet e1 e2, f1, t1) (* should be t1 = t2 *)
   | Exp.Lindex(e1, e1'), Exp.Lindex(e2, e2') ->
       let e1'' = exp_partial_meet e1 e2 in
@@ -1071,7 +1071,7 @@ let rec strexp_partial_join mode (strexp1: Sil.strexp) (strexp2: Sil.strexp) : S
           | JoinState.Post -> Sil.Estruct (IList.rev acc, inst)
         end
     | (fld1, se1):: fld_se_list1', (fld2, se2):: fld_se_list2' ->
-        let comparison = Ident.fieldname_compare fld1 fld2 in
+        let comparison = Ident.compare_fieldname fld1 fld2 in
         if comparison = 0 then
           let strexp' = strexp_partial_join mode se1 se2 in
           let fld_se_list_new = (fld1, strexp') :: acc in
@@ -1135,7 +1135,7 @@ let rec strexp_partial_meet (strexp1: Sil.strexp) (strexp2: Sil.strexp) : Sil.st
     | _, [] ->
         Sil.Estruct (construct Lhs acc fld_se_list1, inst)
     | (fld1, se1):: fld_se_list1', (fld2, se2):: fld_se_list2' ->
-        let comparison = Ident.fieldname_compare fld1 fld2 in
+        let comparison = Ident.compare_fieldname fld1 fld2 in
         if comparison < 0 then
           let se' = strexp_construct_fresh Lhs se1 in
           let acc_new = (fld1, se'):: acc in
diff --git a/infer/src/backend/dotty.ml b/infer/src/backend/dotty.ml
index 20957407c..b241d191a 100644
--- a/infer/src/backend/dotty.ml
+++ b/infer/src/backend/dotty.ml
@@ -384,7 +384,7 @@ let in_cycle cycle edge =
   match cycle with
   | Some cycle' ->
       IList.mem (fun (fn, se) (_,fn',se') ->
-          Ident.fieldname_equal fn fn' && Sil.strexp_equal se se') edge cycle'
+          Ident.equal_fieldname fn fn' && Sil.strexp_equal se se') edge cycle'
   | _ -> false
 
 let node_in_cycle cycle node =
@@ -655,7 +655,7 @@ let filter_useless_spec_dollar_box (nodes: dotty_node list) (links: link list) =
         else boxes_pointing_at n ln' in
   let is_spec_variable = function
     | Exp.Var id ->
-        Ident.is_normal id && Ident.name_equal (Ident.get_name id) Ident.name_spec
+        Ident.is_normal id && Ident.equal_name (Ident.get_name id) Ident.name_spec
     | _ -> false in
   let handle_one_node node =
     match node with
diff --git a/infer/src/backend/errdesc.ml b/infer/src/backend/errdesc.ml
index ebb9bfea2..cbf2005f5 100644
--- a/infer/src/backend/errdesc.ml
+++ b/infer/src/backend/errdesc.ml
@@ -582,7 +582,7 @@ let vpath_find tenv prop _exp : DExp.t option * Typ.t option =
                  | Exp.Sizeof (Tstruct name, _, _) -> (
                      match Tenv.lookup tenv name with
                      | Some {fields} -> (
-                         match IList.find (fun (f', _, _) -> Ident.fieldname_equal f' f) fields with
+                         match IList.find (fun (f', _, _) -> Ident.equal_fieldname f' f) fields with
                          | _, t, _ -> Some t
                          | exception Not_found -> None
                        )
@@ -684,7 +684,7 @@ let explain_dexp_access prop dexp is_nullable =
           (L.d_strln ("lookup_fld: can't find field " ^ Ident.fieldname_to_string f));
         None
     | (f1, se):: fsel' ->
-        if Ident.fieldname_equal f1 f then Some se
+        if Ident.equal_fieldname f1 f then Some se
         else lookup_fld fsel' f in
   let rec lookup_esel esel e = match esel with
     | [] ->
diff --git a/infer/src/backend/match.ml b/infer/src/backend/match.ml
index 0f4c09922..f0bca1a23 100644
--- a/infer/src/backend/match.ml
+++ b/infer/src/backend/match.ml
@@ -74,7 +74,7 @@ let rec exp_match e1 sub vars e2 : (Sil.subst * Ident.t list) option =
       check_equal sub vars e1 e2
   | Exp.Lvar _, _ | _, Exp.Lvar _ ->
       check_equal sub vars e1 e2
-  | Exp.Lfield(e1', fld1, _), Exp.Lfield(e2', fld2, _) when (Ident.fieldname_equal fld1 fld2) ->
+  | Exp.Lfield(e1', fld1, _), Exp.Lfield(e2', fld2, _) when (Ident.equal_fieldname fld1 fld2) ->
       exp_match e1' sub vars e2'
   | Exp.Lfield _, _ | _, Exp.Lfield _ ->
       None
@@ -121,7 +121,7 @@ and fsel_match fsel1 sub vars fsel2 =
       if (Config.abs_struct <= 0) then None
       else Some (sub, vars) (* This can lead to great information loss *)
   | (fld1, se1') :: fsel1', (fld2, se2') :: fsel2' ->
-      let n = Ident.fieldname_compare fld1 fld2 in
+      let n = Ident.compare_fieldname fld1 fld2 in
       if (n = 0) then begin
         match strexp_match se1' sub vars se2' with
         | None -> None
@@ -517,7 +517,7 @@ and generate_todos_from_fel mode todos fel1 fel2 =
   | _, [] ->
       if mode == LFieldForget then Some todos else None
   | (fld1, strexp1) :: fel1', (fld2, strexp2) :: fel2' ->
-      let n = Ident.fieldname_compare fld1 fld2 in
+      let n = Ident.compare_fieldname fld1 fld2 in
       if (n = 0) then
         begin
           match generate_todos_from_strexp mode todos strexp1 strexp2 with
diff --git a/infer/src/backend/prop.ml b/infer/src/backend/prop.ml
index 590b1966e..da214226b 100644
--- a/infer/src/backend/prop.ml
+++ b/infer/src/backend/prop.ml
@@ -1270,7 +1270,7 @@ module Normalize = struct
           (* n1-e1 == n2 -> e1==n1-n2 *)
           (e1, Exp.int (n1 -- n2))
       | Lfield (e1', fld1, _), Lfield (e2', fld2, _) ->
-          if Ident.fieldname_equal fld1 fld2
+          if Ident.equal_fieldname fld1 fld2
           then normalize_eq (e1', e2')
           else eq
       | Lindex (e1', idx1), Lindex (e2', idx2) ->
diff --git a/infer/src/backend/propgraph.ml b/infer/src/backend/propgraph.ml
index 457152a5c..7e83a6e7e 100644
--- a/infer/src/backend/propgraph.ml
+++ b/infer/src/backend/propgraph.ml
@@ -138,7 +138,7 @@ let rec compute_sexp_diff (se1: Sil.strexp) (se2: Sil.strexp) : Obj.t list = mat
 
 and compute_fsel_diff fsel1 fsel2 : Obj.t list = match fsel1, fsel2 with
   | ((f1, se1):: fsel1'), (((f2, se2) as x):: fsel2') ->
-      (match Ident.fieldname_compare f1 f2 with
+      (match Ident.compare_fieldname f1 f2 with
        | n when n < 0 -> compute_fsel_diff fsel1' fsel2
        | 0 -> compute_sexp_diff se1 se2 @ compute_fsel_diff fsel1' fsel2'
        | _ -> (Obj.repr x) :: compute_fsel_diff fsel1 fsel2')
diff --git a/infer/src/backend/prover.ml b/infer/src/backend/prover.ml
index 76f9c3b26..1a5809005 100644
--- a/infer/src/backend/prover.ml
+++ b/infer/src/backend/prover.ml
@@ -1335,7 +1335,7 @@ and struct_imply tenv source calc_missing subs fsel1 fsel2 typ2 : subst2 * ((Ide
   | _, [] -> subs, fsel1, []
   | (f1, se1) :: fsel1', (f2, se2) :: fsel2' ->
       begin
-        match Ident.fieldname_compare f1 f2 with
+        match Ident.compare_fieldname f1 f2 with
         | 0 ->
             let typ' = StructTyp.fld_typ ~lookup ~default:Typ.Tvoid f2 typ2 in
             let subs', se_frame, se_missing =
diff --git a/infer/src/backend/rearrange.ml b/infer/src/backend/rearrange.ml
index 725e43f92..8dcf76fb2 100644
--- a/infer/src/backend/rearrange.ml
+++ b/infer/src/backend/rearrange.ml
@@ -105,14 +105,14 @@ let rec create_struct_values pname tenv orig_prop footprint_part kind max_stamp
     | Tstruct name, (Off_fld (f, _)) :: off' -> (
         match Tenv.lookup tenv name with
         | Some ({ fields; statics; } as struct_typ) -> (
-            match IList.find (fun (f', _, _) -> Ident.fieldname_equal f f') (fields @ statics) with
+            match IList.find (fun (f', _, _) -> Ident.equal_fieldname f f') (fields @ statics) with
             | _, t', _ ->
                 let atoms', se', res_t' =
                   create_struct_values
                     pname tenv orig_prop footprint_part kind max_stamp t' off' inst in
                 let se = Sil.Estruct ([(f, se')], inst) in
                 let replace_typ_of_f (f', t', a') =
-                  if Ident.fieldname_equal f f' then (f, res_t', a') else (f', t', a') in
+                  if Ident.equal_fieldname f f' then (f, res_t', a') else (f', t', a') in
                 let fields' =
                   IList.sort StructTyp.fld_typ_ann_compare (IList.map replace_typ_of_f fields) in
                 ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
@@ -206,10 +206,10 @@ let rec _strexp_extend_values
   | (Off_fld (f, _)) :: off', Sil.Estruct (fsel, inst'), Tstruct name -> (
       match Tenv.lookup tenv name with
       | Some ({ fields; statics; } as struct_typ) -> (
-          let replace_fv new_v fv = if Ident.fieldname_equal (fst fv) f then (f, new_v) else fv in
-          match IList.find (fun (f', _, _) -> Ident.fieldname_equal f f') (fields @ statics) with
+          let replace_fv new_v fv = if Ident.equal_fieldname (fst fv) f then (f, new_v) else fv in
+          match IList.find (fun (f', _, _) -> Ident.equal_fieldname f f') (fields @ statics) with
           | _, typ', _ -> (
-              match IList.find (fun (f', _) -> Ident.fieldname_equal f f') fsel with
+              match IList.find (fun (f', _) -> Ident.equal_fieldname f f') fsel with
               | _, se' ->
                   let atoms_se_typ_list' =
                     _strexp_extend_values
@@ -232,7 +232,7 @@ let rec _strexp_extend_values
                       pname tenv orig_prop footprint_part kind max_stamp typ' off' inst in
                   let res_fsel' = IList.sort Sil.fld_strexp_compare ((f, se'):: fsel) in
                   let replace_fta (f', t', a') =
-                    if Ident.fieldname_equal f' f then (f, res_typ', a') else (f', t', a') in
+                    if Ident.equal_fieldname f' f then (f, res_typ', a') else (f', t', a') in
                   let fields' =
                     IList.sort StructTyp.fld_typ_ann_compare (IList.map replace_fta fields) in
                   ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
@@ -470,7 +470,7 @@ let prop_iter_check_fields_ptsto_shallow tenv iter lexp =
         (match se with
          | Sil.Estruct (fsel, _) ->
              (try
-                let _, se' = IList.find (fun (fld', _) -> Ident.fieldname_equal fld fld') fsel in
+                let _, se' = IList.find (fun (fld', _) -> Ident.equal_fieldname fld fld') fsel in
                 check_offset se' off'
               with Not_found -> Some fld)
          | _ -> Some fld)
@@ -534,7 +534,7 @@ let prop_iter_extend_ptsto pname tenv orig_prop iter lexp inst =
           pname tenv orig_prop false extend_kind max_stamp se te offset inst in
       IList.map (atoms_se_te_to_iter e) atoms_se_te_list in
     let res_iter_list =
-      if Ident.kind_equal extend_kind Ident.kprimed
+      if Ident.equal_kind extend_kind Ident.kprimed
       then iter_list (* normal part already extended: nothing to do *)
       else (* extend footprint part *)
         let atoms_fp_sigma_list =
@@ -842,7 +842,7 @@ let add_guarded_by_constraints tenv prop lexp pdesc =
                 IList.exists
                   (fun (fld, strexp) -> match strexp with
                      | Sil.Eexp (rhs_exp, _) ->
-                         Exp.equal exp rhs_exp && not (Ident.fieldname_equal fld accessed_fld)
+                         Exp.equal exp rhs_exp && not (Ident.equal_fieldname fld accessed_fld)
                      | _ ->
                          false)
                   flds
@@ -1119,7 +1119,7 @@ let type_at_offset tenv texp off =
     | (Off_fld (f, _)) :: off', Tstruct name -> (
         match Tenv.lookup tenv name with
         | Some { fields } -> (
-            match IList.find (fun (f', _, _) -> Ident.fieldname_equal f f') fields with
+            match IList.find (fun (f', _, _) -> Ident.equal_fieldname f f') fields with
             | _, typ', _ -> strip_offset off' typ'
             | exception Not_found -> None
           )
diff --git a/infer/src/backend/symExec.ml b/infer/src/backend/symExec.ml
index 068d96308..c944abe85 100644
--- a/infer/src/backend/symExec.ml
+++ b/infer/src/backend/symExec.ml
@@ -17,7 +17,7 @@ module F = Format
 
 let rec fldlist_assoc fld = function
   | [] -> raise Not_found
-  | (fld', x, _):: l -> if Ident.fieldname_equal fld fld' then x else fldlist_assoc fld l
+  | (fld', x, _):: l -> if Ident.equal_fieldname fld fld' then x else fldlist_assoc fld l
 
 let unroll_type tenv (typ: Typ.t) (off: Sil.offset) =
   let fail fld_to_string fld =
@@ -141,17 +141,17 @@ let rec apply_offlist
       match Tenv.lookup tenv name with
       | Some ({fields} as struct_typ) -> (
           let t' = unroll_type tenv typ (Sil.Off_fld (fld, fld_typ)) in
-          match IList.find (fun fse -> Ident.fieldname_equal fld (fst fse)) fsel with
+          match IList.find (fun fse -> Ident.equal_fieldname fld (fst fse)) fsel with
           | _, se' ->
               let res_e', res_se', res_t', res_pred_insts_op' =
                 apply_offlist
                   pdesc tenv p fp_root nullify_struct
                   (root_lexp, se', t') offlist' f inst lookup_inst in
               let replace_fse fse =
-                if Ident.fieldname_equal fld (fst fse) then (fld, res_se') else fse in
+                if Ident.equal_fieldname fld (fst fse) then (fld, res_se') else fse in
               let res_se = Sil.Estruct (IList.map replace_fse fsel, inst') in
               let replace_fta (f, t, a) =
-                if Ident.fieldname_equal fld f then (fld, res_t', a) else (f, t, a) in
+                if Ident.equal_fieldname fld f then (fld, res_t', a) else (f, t, a) in
               let fields' = IList.map replace_fta fields in
               ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
               (res_e', res_se, typ, res_pred_insts_op')
diff --git a/infer/src/backend/tabulation.ml b/infer/src/backend/tabulation.ml
index 857c20366..2fe5b89c6 100644
--- a/infer/src/backend/tabulation.ml
+++ b/infer/src/backend/tabulation.ml
@@ -418,7 +418,7 @@ let rec fsel_star_fld fsel1 fsel2 = match fsel1, fsel2 with
   | [], fsel2 -> fsel2
   | fsel1,[] -> fsel1
   | (f1, se1):: fsel1', (f2, se2):: fsel2' ->
-      (match Ident.fieldname_compare f1 f2 with
+      (match Ident.compare_fieldname f1 f2 with
        | 0 -> (f1, sexp_star_fld se1 se2) :: fsel_star_fld fsel1' fsel2'
        | n when n < 0 -> (f1, se1) :: fsel_star_fld fsel1' fsel2
        | _ -> (f2, se2) :: fsel_star_fld fsel1 fsel2')
@@ -461,7 +461,7 @@ let texp_star tenv texp1 texp2 =
     | [], _ -> true
     | _, [] -> false
     | (f1, _, _):: ftal1', (f2, _, _):: ftal2' ->
-        begin match Ident.fieldname_compare f1 f2 with
+        begin match Ident.compare_fieldname f1 f2 with
           | n when n < 0 -> false
           | 0 -> ftal_sub ftal1' ftal2'
           | _ -> ftal_sub ftal1 ftal2' end in
diff --git a/infer/src/backend/taint.ml b/infer/src/backend/taint.ml
index 73dd123ae..171165b00 100644
--- a/infer/src/backend/taint.ml
+++ b/infer/src/backend/taint.ml
@@ -353,7 +353,7 @@ let tainted_params callee_pname =
 
 let has_taint_annotation fieldname (struct_typ: StructTyp.t) =
   let fld_has_taint_annot (fname, _, annot) =
-    Ident.fieldname_equal fieldname fname &&
+    Ident.equal_fieldname fieldname fname &&
     (Annotations.ia_is_privacy_source annot || Annotations.ia_is_integrity_source annot) in
   IList.exists fld_has_taint_annot struct_typ.fields ||
   IList.exists fld_has_taint_annot struct_typ.statics
diff --git a/infer/src/checkers/accessPath.ml b/infer/src/checkers/accessPath.ml
index 5f10a9946..fced84744 100644
--- a/infer/src/checkers/accessPath.ml
+++ b/infer/src/checkers/accessPath.ml
@@ -42,7 +42,7 @@ let access_compare access1 access2 =
   else
     match access1, access2 with
     | FieldAccess (f1, typ1), FieldAccess (f2, typ2) ->
-        let n = Ident.fieldname_compare f1 f2 in
+        let n = Ident.compare_fieldname f1 f2 in
         if n <> 0
         then n
         else Typ.compare typ1 typ2
diff --git a/infer/src/checkers/patternMatch.ml b/infer/src/checkers/patternMatch.ml
index 76def35e0..6f11d664c 100644
--- a/infer/src/checkers/patternMatch.ml
+++ b/infer/src/checkers/patternMatch.ml
@@ -123,7 +123,7 @@ let get_field_type_name tenv
   | Tstruct name | Tptr (Tstruct name, _) -> (
       match Tenv.lookup tenv name with
       | Some { fields } -> (
-          match IList.find (function | (fn, _, _) -> Ident.fieldname_equal fn fieldname) fields with
+          match IList.find (function | (fn, _, _) -> Ident.equal_fieldname fn fieldname) fields with
           | _, ft, _ -> Some (get_type_name ft)
           | exception Not_found -> None
         )
diff --git a/infer/src/clang/cFrontend_utils.ml b/infer/src/clang/cFrontend_utils.ml
index c646eee36..4f55e8409 100644
--- a/infer/src/clang/cFrontend_utils.ml
+++ b/infer/src/clang/cFrontend_utils.ml
@@ -581,7 +581,7 @@ struct
       match field_tuple, l with
       | (field, typ, annot), ((old_field, old_typ, old_annot) as old_field_tuple :: rest) ->
           let ret_list, ret_found = replace_field field_tuple rest found in
-          if Ident.fieldname_equal field old_field && Typ.equal typ old_typ then
+          if Ident.equal_fieldname field old_field && Typ.equal typ old_typ then
             let annotations = append_no_duplicates_annotations annot old_annot in
             (field, typ, annotations) :: ret_list, true
           else old_field_tuple :: ret_list, ret_found
@@ -599,7 +599,7 @@ struct
 
   let sort_fields fields =
     let compare (name1, _, _) (name2, _, _) =
-      Ident.fieldname_compare name1 name2 in
+      Ident.compare_fieldname name1 name2 in
     IList.sort compare fields
 
 
diff --git a/infer/src/eradicate/typeErr.ml b/infer/src/eradicate/typeErr.ml
index 94dacfd4b..79465bd26 100644
--- a/infer/src/eradicate/typeErr.ml
+++ b/infer/src/eradicate/typeErr.ml
@@ -86,28 +86,28 @@ module H = Hashtbl.Make(struct
       | Condition_redundant _, _
       | _, Condition_redundant _ -> false
       | Field_not_initialized (fn1, pn1), Field_not_initialized (fn2, pn2) ->
-          Ident.fieldname_equal fn1 fn2 &&
+          Ident.equal_fieldname fn1 fn2 &&
           Procname.equal pn1 pn2
       | Field_not_initialized (_, _), _
       | _, Field_not_initialized (_, _) -> false
       | Field_not_mutable (fn1, _), Field_not_mutable (fn2, _) ->
-          Ident.fieldname_equal fn1 fn2
+          Ident.equal_fieldname fn1 fn2
       | Field_not_mutable _, _
       | _, Field_not_mutable _ -> false
       | Field_annotation_inconsistent (ann1, fn1, _),
         Field_annotation_inconsistent (ann2, fn2, _) ->
           ann1 = ann2 &&
-          Ident.fieldname_equal fn1 fn2
+          Ident.equal_fieldname fn1 fn2
       | Field_annotation_inconsistent _, _
       | _, Field_annotation_inconsistent _ -> false
       | Field_over_annotated (fn1, pn1), Field_over_annotated (fn2, pn2) ->
-          Ident.fieldname_equal fn1 fn2 &&
+          Ident.equal_fieldname fn1 fn2 &&
           Procname.equal pn1 pn2
       | Field_over_annotated (_, _), _
       | _, Field_over_annotated (_, _) -> false
       | Null_field_access (so1, fn1, _, ii1), Null_field_access (so2, fn2, _, ii2) ->
           (opt_equal string_equal) so1 so2 &&
-          Ident.fieldname_equal fn1 fn2 &&
+          Ident.equal_fieldname fn1 fn2 &&
           bool_equal ii1 ii2
       | Null_field_access _, _
       | _, Null_field_access _ -> false
diff --git a/infer/src/eradicate/typeOrigin.ml b/infer/src/eradicate/typeOrigin.ml
index de5d34409..1796d1c1a 100644
--- a/infer/src/eradicate/typeOrigin.ml
+++ b/infer/src/eradicate/typeOrigin.ml
@@ -45,7 +45,7 @@ let equal o1 o2 = match o1, o2 with
   | Const _, _
   | _, Const _ -> false
   | Field (fn1, loc1), Field (fn2, loc2) ->
-      Ident.fieldname_equal fn1 fn2 &&
+      Ident.equal_fieldname fn1 fn2 &&
       Location.equal loc1 loc2
   | Field _, _
   | _, Field _ -> false