Deprecate more IList functions and use Core List instead

Reviewed By: jberdine

Differential Revision: D4501499

fbshipit-source-id: 21ae309

infer/src/IR/Cfg.re

@@ -74,7 +74,7 @@ let get_all_procs cfg => {
 
 
 /** Get the procedures whose body is defined in this cfg */
-let get_defined_procs cfg => IList.filter Procdesc.is_defined (get_all_procs cfg);
+let get_defined_procs cfg => List.filter f::Procdesc.is_defined (get_all_procs cfg);
 
 
 /** checks whether a cfg is connected or not */

infer/src/IR/Cg.re

@@ -223,7 +223,8 @@ let get_all_nodes (g: t) => {
   IList.map (fun node => (node, get_calls g node)) nodes
 };
 
-let get_nodes_and_calls (g: t) => IList.filter (fun (n, _) => node_defined g n) (get_all_nodes g);
+let get_nodes_and_calls (g: t) =>
+  List.filter f::(fun (n, _) => node_defined g n) (get_all_nodes g);
 
 let node_get_num_ancestors g n => (n, Procname.Set.cardinal (get_ancestors g n));
 
@@ -331,7 +332,7 @@ let get_nodes_and_edges (g: t) :nodes_and_edges => {
 let get_defined_nodes (g: t) => {
   let (nodes, _) = get_nodes_and_edges g;
   let get_node (node, _) => node;
-  IList.map get_node (IList.filter (fun (_, defined) => defined) nodes)
+  IList.map get_node (List.filter f::(fun (_, defined) => defined) nodes)
 };
 
 

infer/src/IR/Localise.ml

@@ -140,13 +140,11 @@ module Tags = struct
   let create () = ref []
   let add tags tag value = tags := (tag, value) :: !tags
   let update tags tag value =
-    let tags' = IList.filter (fun (t, _) -> t <> tag) tags in
+    let tags' = List.filter ~f:(fun (t, _) -> t <> tag) tags in
     (tag, value) :: tags'
   let get tags tag =
-    try
+    List.find ~f:(fun (t, _) -> String.equal t tag) tags |>
-      let (_, v) = IList.find (fun (t, _) -> String.equal t tag) tags in
+    Option.map ~f:snd
-      Some v
-    with Not_found -> None
 end
 
 module BucketLevel = struct
@@ -164,10 +162,9 @@ let error_desc_extract_tag_value err_desc tag_to_extract =
     match v with
     | (t, _) when String.equal t tag -> true
     | _ -> false in
-  try
+  match List.find ~f:(find_value tag_to_extract) err_desc.tags with
-    let _, s = IList.find (find_value tag_to_extract) err_desc.tags in
+  | Some (_, s) -> s
-    s
+  | None -> ""
-  with Not_found -> ""
 
 let error_desc_to_tag_value_pairs err_desc = err_desc.tags
 
@@ -193,8 +190,8 @@ let error_desc_set_bucket err_desc bucket show_in_message =
 (** get the value tag, if any *)
 let get_value_line_tag tags =
   try
-    let value = snd (IList.find (fun (tag, _) -> String.equal tag Tags.value) tags) in
+    let value = snd (List.find_exn ~f:(fun (tag, _) -> String.equal tag Tags.value) tags) in
-    let line = snd (IList.find (fun (tag, _) -> String.equal tag Tags.line) tags) in
+    let line = snd (List.find_exn ~f:(fun (tag, _) -> String.equal tag Tags.line) tags) in
     Some [value; line]
   with Not_found -> None
 

infer/src/IR/Objc_models.ml

@@ -238,11 +238,10 @@ struct
     function_arg_is_cftype typ && String.equal funct cf_release
 
   let is_core_graphics_release typ funct =
-    try
+    let f lib =
-      let cg_typ = IList.find
+      String.equal funct (lib ^ upper_release) &&
-          (fun lib -> (String.equal funct (lib^upper_release))) core_graphics_types in
+      String.is_substring ~substring:(lib ^ ref) typ in
-      (String.is_substring ~substring:(cg_typ^ref) typ)
+    List.exists ~f core_graphics_types
-    with Not_found -> false
 
 (*
   let function_arg_is_core_pgraphics typ =

infer/src/IR/Procdesc.re

@@ -89,7 +89,7 @@ let module Node = {
           NodeSet.singleton n
         } else {
           NodeSet.union
-            acc (slice_nodes (IList.filter (fun s => not (NodeSet.mem s !visited)) n.succs))
+            acc (slice_nodes (List.filter f::(fun s => not (NodeSet.mem s !visited)) n.succs))
         }
       };
       IList.fold_left do_node NodeSet.empty nodes
@@ -105,7 +105,7 @@ let module Node = {
           NodeSet.singleton n
         } else {
           NodeSet.union
-            acc (slice_nodes (IList.filter (fun s => not (NodeSet.mem s !visited)) n.preds))
+            acc (slice_nodes (List.filter f::(fun s => not (NodeSet.mem s !visited)) n.preds))
         }
       };
       IList.fold_left do_node NodeSet.empty nodes
@@ -132,9 +132,9 @@ let module Node = {
     let visited = ref NodeSet.empty;
     let rec nodes n => {
       visited := NodeSet.add n !visited;
-      let succs = IList.filter (fun n => not (NodeSet.mem n !visited)) (generator n);
+      let succs = List.filter f::(fun n => not (NodeSet.mem n !visited)) (generator n);
-      switch (IList.length succs) {
+      switch succs {
-      | 1 => [n, ...nodes (IList.hd succs)]
+      | [hd] => [n, ...nodes hd]
       | _ => [n]
       }
     };

infer/src/IR/Sil.re

@@ -692,22 +692,23 @@ let module Predicates: {
       Can be applied only once, as it destroys the todo list */
   let iter (env: env) f f_dll =>
     while (env.todo != [] || env.todo_dll != []) {
-      if (env.todo != []) {
+      switch env.todo {
-        let hpara = IList.hd env.todo;
+      | [hpara, ...todo'] =>
-        let () = env.todo = IList.tl env.todo;
+        env.todo = todo';
         let (n, emitted) = HparaHash.find env.hash hpara;
         if (not emitted) {
           f n hpara
         }
-      } else if (
+      | [] =>
-        env.todo_dll != []
+        switch env.todo_dll {
-      ) {
+        | [hpara_dll, ...todo_dll'] =>
-        let hpara_dll = IList.hd env.todo_dll;
+          env.todo_dll = todo_dll';
-        let () = env.todo_dll = IList.tl env.todo_dll;
           let (n, emitted) = HparaDllHash.find env.hash_dll hpara_dll;
           if (not emitted) {
             f_dll n hpara_dll
           }
+        | [] => ()
+        }
       }
     };
 };
@@ -1223,7 +1224,7 @@ let hpred_get_lexp acc =>
 
 let hpred_list_get_lexps (filter: Exp.t => bool) (hlist: list hpred) :list Exp.t => {
   let lexps = IList.fold_left hpred_get_lexp [] hlist;
-  IList.filter filter lexps
+  List.filter f::filter lexps
 };
 
 
@@ -1246,7 +1247,7 @@ let rec exp_fpv e =>
   | Sizeof _ _ _ => []
   };
 
-let exp_list_fpv el => IList.flatten (IList.map exp_fpv el);
+let exp_list_fpv el => List.concat (IList.map exp_fpv el);
 
 let atom_fpv =
   fun
@@ -1260,12 +1261,12 @@ let rec strexp_fpv =
   | Eexp e _ => exp_fpv e
   | Estruct fld_se_list _ => {
       let f (_, se) => strexp_fpv se;
-      IList.flatten (IList.map f fld_se_list)
+      List.concat (IList.map f fld_se_list)
     }
   | Earray len idx_se_list _ => {
       let fpv_in_len = exp_fpv len;
       let f (idx, se) => exp_fpv idx @ strexp_fpv se;
-      fpv_in_len @ IList.flatten (IList.map f idx_se_list)
+      fpv_in_len @ List.concat (IList.map f idx_se_list)
     };
 
 let rec hpred_fpv =
@@ -1286,7 +1287,7 @@ let rec hpred_fpv =
     analysis. In interprocedural analysis, we should consider the issue
     of scopes of program variables. */
 and hpara_fpv para => {
-  let fpvars_in_body = IList.flatten (IList.map hpred_fpv para.body);
+  let fpvars_in_body = List.concat (IList.map hpred_fpv para.body);
   switch fpvars_in_body {
   | [] => []
   | _ => assert false
@@ -1297,7 +1298,7 @@ and hpara_fpv para => {
     analysis. In interprocedural analysis, we should consider the issue
     of scopes of program variables. */
 and hpara_dll_fpv para => {
-  let fpvars_in_body = IList.flatten (IList.map hpred_fpv para.body_dll);
+  let fpvars_in_body = List.concat (IList.map hpred_fpv para.body_dll);
   switch fpvars_in_body {
   | [] => []
   | _ => assert false
@@ -1391,11 +1392,11 @@ let fav_imperative_to_functional f x => {
 
 
 /** [fav_filter_ident fav f] only keeps [id] if [f id] is true. */
-let fav_filter_ident fav filter => fav := IList.filter filter !fav;
+let fav_filter_ident fav filter => fav := List.filter f::filter !fav;
 
 
 /** Like [fav_filter_ident] but return a copy. */
-let fav_copy_filter_ident fav filter => ref (IList.filter filter !fav);
+let fav_copy_filter_ident fav filter => ref (List.filter f::filter !fav);
 
 
 /** checks whether every element in l1 appears l2 **/
@@ -1730,17 +1731,17 @@ let sub_symmetric_difference sub1_in sub2_in => {
 
 /** [sub_find filter sub] returns the expression associated to the first identifier
     that satisfies [filter]. Raise [Not_found] if there isn't one. */
-let sub_find filter (sub: subst) => snd (IList.find (fun (i, _) => filter i) sub);
+let sub_find filter (sub: subst) => snd (List.find_exn f::(fun (i, _) => filter i) sub);
 
 
 /** [sub_filter filter sub] restricts the domain of [sub] to the
     identifiers satisfying [filter]. */
-let sub_filter filter (sub: subst) => IList.filter (fun (i, _) => filter i) sub;
+let sub_filter filter (sub: subst) => List.filter f::(fun (i, _) => filter i) sub;
 
 
 /** [sub_filter_pair filter sub] restricts the domain of [sub] to the
     identifiers satisfying [filter(id, sub(id))]. */
-let sub_filter_pair = IList.filter;
+let sub_filter_pair = List.filter;
 
 
 /** [sub_range_partition filter sub] partitions [sub] according to
@@ -1795,7 +1796,7 @@ let sub_fav_add fav (sub: subst) =>
     )
     sub;
 
-let sub_fpv (sub: subst) => IList.flatten (IList.map (fun (_, e) => exp_fpv e) sub);
+let sub_fpv (sub: subst) => List.concat (IList.map (fun (_, e) => exp_fpv e) sub);
 
 
 /** Substitutions do not contain binders */
@@ -2235,12 +2236,7 @@ let hpred_sub subst => {
 
 /** {2 Functions for replacing occurrences of expressions.} */
 let exp_replace_exp epairs e =>
-  try {
+  List.find f::(fun (e1, _) => Exp.equal e e1) epairs |> Option.value_map f::snd default::e;
-    let (_, e') = IList.find (fun (e1, _) => Exp.equal e e1) epairs;
-    e'
-  } {
-  | Not_found => e
-  };
 
 let atom_replace_exp epairs atom => atom_expmap (fun e => exp_replace_exp epairs e) atom;
 
@@ -2382,13 +2378,13 @@ let sigma_to_sigma_ne sigma :list (list atom, list hpred) =>
           ([Aeq e1 e2, ...eqs], sigma),
           (eqs, [Hlseg Lseg_NE para e1 e2 el, ...sigma])
         ];
-        IList.flatten (IList.map g eqs_sigma_list)
+        List.concat (IList.map g eqs_sigma_list)
       | Hdllseg Lseg_PE para_dll e1 e2 e3 e4 el =>
         let g (eqs, sigma) => [
           ([Aeq e1 e3, Aeq e2 e4, ...eqs], sigma),
           (eqs, [Hdllseg Lseg_NE para_dll e1 e2 e3 e4 el, ...sigma])
         ];
-        IList.flatten (IList.map g eqs_sigma_list)
+        List.concat (IList.map g eqs_sigma_list)
       };
     IList.fold_left f [([], [])] sigma
   } else {

infer/src/IR/Sil.rei

@@ -716,7 +716,7 @@ let sub_filter: (Ident.t => bool) => subst => subst;
 
 /** [sub_filter_exp filter sub] restricts the domain of [sub] to the
     identifiers satisfying [filter(id, sub(id))]. */
-let sub_filter_pair: ((Ident.t, Exp.t) => bool) => subst => subst;
+let sub_filter_pair: subst => f::((Ident.t, Exp.t) => bool) => subst;
 
 
 /** [sub_range_partition filter sub] partitions [sub] according to

infer/src/IR/StructTyp.re

@@ -111,9 +111,8 @@ 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.equal_fieldname f fn) fields)) {
+      List.find f::(fun (f, _, _) => Ident.equal_fieldname f fn) fields |>
-      | Not_found => default
+      Option.value_map f::snd3 default::default
-      }
     | None => default
     }
   | _ => default
@@ -125,13 +124,8 @@ let get_field_type_and_annotation lookup::lookup fn (typ: Typ.t) =>
   | Tptr (Tstruct name) _ =>
     switch (lookup name) {
     | Some {fields, statics} =>
-      try {
+      List.find_map
-        let (_, t, a) =
+        f::(fun (f, t, a) => Ident.equal_fieldname f fn ? Some (t, a) : None) (fields @ statics)
-          IList.find (fun (f, _, _) => Ident.equal_fieldname f fn) (fields @ statics);
-        Some (t, a)
-      } {
-      | Not_found => None
-      }
     | None => None
     }
   | _ => None

infer/src/IR/Subtype.re

@@ -153,7 +153,7 @@ let is_instof t => equal_kind (snd t) INSTOF;
 
 let list_intersect equal l1 l2 => {
   let in_l2 a => List.mem equal::equal l2 a;
-  IList.filter in_l2 l1
+  List.filter f::in_l2 l1
 };
 
 let join_flag flag1 flag2 =>

infer/src/IR/Tenv.re

@@ -93,8 +93,8 @@ let add tenv name struct_typ => TypenameHash.replace tenv name struct_typ;
 /** Get method that is being overriden by java_pname (if any) **/
 let get_overriden_method tenv pname_java => {
   let struct_typ_get_method_by_name (struct_typ: StructTyp.t) method_name =>
-    IList.find
+    List.find_exn
-      (fun meth => String.equal method_name (Procname.get_method meth)) struct_typ.methods;
+      f::(fun meth => String.equal method_name (Procname.get_method meth)) struct_typ.methods;
   let rec get_overriden_method_in_supers pname_java supers =>
     switch supers {
     | [superclass, ...supers_tail] =>

infer/src/backend/Attribute.ml

@@ -38,7 +38,7 @@ let add_or_replace_check_changed tenv check_attribute_change prop atom0 =
   | Sil.Apred (att0, ((_ :: _) as exps0)) | Anpred (att0, ((_ :: _) as exps0)) ->
       let pairs =
         IList.map (fun e -> (e, Prop.exp_normalize_prop tenv prop e)) exps0 in
-      let _, nexp = IList.hd pairs in (* len exps0 > 0 by match *)
+      let _, nexp = List.hd_exn pairs in (* len exps0 > 0 by match *)
       let natom = Sil.atom_replace_exp pairs atom0 in
       let atom_map = function
         | Sil.Apred (att, exp :: _) | Anpred (att, exp :: _)
@@ -69,7 +69,7 @@ let get_all (prop: 'a Prop.t) =
 
 (** Get all the attributes of the prop *)
 let get_for_symb prop att =
-  IList.filter (function
+  List.filter ~f:(function
       | Sil.Apred (att', _) | Anpred (att', _) -> PredSymb.equal att' att
       | _ -> false
     ) prop.Prop.pi
@@ -86,14 +86,12 @@ let get_for_exp tenv (prop: 'a Prop.t) exp =
 
 let get tenv prop exp category =
   let atts = get_for_exp tenv prop exp in
-  try
+  List.find
-    Some
+    ~f:(function
-      (IList.find (function
         | Sil.Apred (att, _) | Anpred (att, _) ->
             PredSymb.equal_category (PredSymb.to_category att) category
-           | _ -> false
+        | _ -> false)
-         ) atts)
+    atts
-  with Not_found -> None
 
 let get_undef tenv prop exp =
   get tenv prop exp ACundef
@@ -248,11 +246,15 @@ let find_arithmetic_problem tenv proc_node_session prop exp =
     | Exp.Sizeof (_, None, _) -> ()
     | Exp.Sizeof (_, Some len, _) -> walk len in
   walk exp;
-  try Some (Div0 (IList.find check_zero !exps_divided)), !res
+  let problem_opt =
-  with Not_found ->
+    match (List.find ~f:check_zero !exps_divided, !uminus_unsigned) with
-    (match !uminus_unsigned with
+    | Some e, _ ->
-     | (e, t):: _ -> Some (UminusUnsigned (e, t)), !res
+        Some (Div0 e)
-     | _ -> None, !res)
+    | None, (e, t):: _ ->
+        Some (UminusUnsigned (e, t))
+    | None, [] ->
+        None in
+  problem_opt, !res
 
 (** Deallocate the stack variables in [pvars], and replace them by normal variables.
     Return the list of stack variables whose address was still present after deallocation. *)

infer/src/backend/BuiltinDefn.ml

@@ -62,29 +62,30 @@ let return_result tenv e prop ret_id =
 let add_array_to_prop tenv pdesc prop_ lexp typ =
   let pname = Procdesc.get_proc_name pdesc in
   let n_lexp, prop = check_arith_norm_exp tenv pname lexp prop_ in
-  begin
+  let hpred_opt =
-    try
+    List.find
-      let hpred = IList.find (function
+      ~f:(function
           | Sil.Hpointsto(e, _, _) -> Exp.equal e n_lexp
-          | _ -> false) prop.Prop.sigma in
+          | _ -> false)
-      match hpred with
+      prop.Prop.sigma in
-      | Sil.Hpointsto(_, Sil.Earray (len, _, _), _) ->
+  match hpred_opt with
+  | Some (Sil.Hpointsto (_, Sil.Earray (len, _, _), _)) ->
       Some (len, prop)
-      | _ -> None (* e points to something but not an array *)
+  | Some _ ->
-    with Not_found -> (* e is not allocated, so we can add the array *)
+      None (* e points to something but not an array *)
-    match extract_array_type typ with
+  | None ->
-    | Some arr_typ ->
+      extract_array_type typ |>
+      Option.map ~f:(fun arr_typ ->
           let len = Exp.Var (Ident.create_fresh Ident.kfootprint) in
           let s = mk_empty_array_rearranged len in
-        let hpred = Prop.mk_ptsto tenv n_lexp s (Exp.Sizeof (arr_typ, Some len, Subtype.exact)) in
+          let hpred =
+            Prop.mk_ptsto tenv n_lexp s (Exp.Sizeof (arr_typ, Some len, Subtype.exact)) in
           let sigma = prop.Prop.sigma in
           let sigma_fp = prop.Prop.sigma_fp in
           let prop'= Prop.set prop ~sigma:(hpred:: sigma) in
           let prop''= Prop.set prop' ~sigma_fp:(hpred:: sigma_fp) in
           let prop''= Prop.normalize tenv prop'' in
-        Some (len, prop'')
+          (len, prop''))
-    | _ -> None
-  end
 
 (* Add an array in prop if it is not allocated.*)
 let execute___require_allocated_array { Builtin.tenv; pdesc; prop_; path; args; }
@@ -146,12 +147,13 @@ let is_undefined_opt tenv prop n_lexp =
     it doesn't appear already in the heap. *)
 let create_type tenv n_lexp typ prop =
   let prop_type =
-    try
+    match
-      let _ = IList.find (function
+      List.find ~f:(function
           | Sil.Hpointsto(e, _, _) -> Exp.equal e n_lexp
-          | _ -> false) prop.Prop.sigma in
+          | _ -> false) prop.Prop.sigma with
+    | Some _ ->
         prop
-    with Not_found ->
+    | None ->
         let mhpred =
           match typ with
           | Typ.Tptr (typ', _) ->
@@ -198,17 +200,15 @@ let execute___get_type_of { Builtin.pdesc; tenv; prop_; path; ret_id; args; }
       let n_lexp, prop = check_arith_norm_exp tenv pname lexp prop_ in
       let props = create_type tenv n_lexp typ prop in
       let aux prop =
-        begin
+        let hpred_opt =
-          try
+          List.find_map ~f:(function
-            let hpred = IList.find (function
+              | Sil.Hpointsto(e, _, texp) when Exp.equal e n_lexp -> Some texp
-                | Sil.Hpointsto(e, _, _) -> Exp.equal e n_lexp
+              | _ -> None) prop.Prop.sigma in
-                | _ -> false) prop.Prop.sigma in
+        match hpred_opt with
-            match hpred with
+        | Some texp ->
-            | Sil.Hpointsto(_, _, texp) ->
+            ((return_result tenv texp prop ret_id), path)
-                (return_result tenv texp prop ret_id), path
+        | None ->
-            | _ -> assert false
+            ((return_result tenv Exp.zero prop ret_id), path) in
-          with Not_found -> (return_result tenv Exp.zero prop ret_id), path
-        end in
       (IList.map aux props)
   | _ -> raise (Exceptions.Wrong_argument_number __POS__)
 
@@ -252,12 +252,11 @@ let execute___instanceof_cast ~instof
         if Exp.equal texp2 Exp.zero then
           [(return_result tenv Exp.zero prop ret_id, path)]
         else
-          begin
+          let res_opt =
-            try
+            List.find ~f:(function
-              let hpred = IList.find (function
                 | Sil.Hpointsto (e1, _, _) -> Exp.equal e1 val1
-                  | _ -> false) prop.Prop.sigma in
+                | _ -> false) prop.Prop.sigma |>
-              match hpred with
+            Option.map ~f:(function
                 | Sil.Hpointsto (_, _, texp1) ->
                     let pos_type_opt, neg_type_opt =
                       Prover.Subtyping_check.subtype_case_analysis tenv texp1 texp2 in
@@ -291,11 +290,14 @@ let execute___instanceof_cast ~instof
                           | None -> mk_res pos_type_opt val1
                       end
                 | _ -> []
-            with Not_found ->
+              ) in
-              [(return_result tenv val1 prop ret_id, path)]
+          match res_opt with
-          end in
+          | Some res ->
+              res
+          | None ->
+              [(return_result tenv val1 prop ret_id, path)] in
       let props = create_type tenv val1 typ1 prop in
-      IList.flatten (IList.map exe_one_prop props)
+      List.concat (IList.map exe_one_prop props)
   | _ -> raise (Exceptions.Wrong_argument_number __POS__)
 
 let execute___instanceof builtin_args
@@ -399,9 +401,11 @@ let execute___get_hidden_field { Builtin.tenv; pdesc; prop_; path; ret_id; args;
         | Sil.Hpointsto(e, Sil.Estruct (fsel, _), _)
           when Exp.equal e n_lexp && not in_foot && has_fld_hidden fsel ->
             let set_ret_val () =
-              match IList.find filter_fld_hidden fsel with
+              match List.find ~f:filter_fld_hidden fsel with
-              | _, Sil.Eexp(e, _) -> ret_val := Some e
+              | Some (_, Sil.Eexp(e, _)) ->
-              | _ -> () in
+                  ret_val := Some e
+              | _ ->
+                  () in
             set_ret_val();
             hpred
         | _ -> hpred in
@@ -430,7 +434,7 @@ let execute___set_hidden_field { Builtin.tenv; pdesc; prop_; path; args; }
             let se = Sil.Eexp(n_lexp2, Sil.inst_none) in
             let fsel' =
               (Ident.fieldname_hidden, se) ::
-              (IList.filter (fun x -> not (filter_fld_hidden x)) fsel) in
+              (List.filter ~f:(fun x -> not (filter_fld_hidden x)) fsel) in
             Sil.Hpointsto(e, Sil.Estruct (fsel', inst), texp)
         | Sil.Hpointsto(e, Sil.Estruct (fsel, inst), texp)
           when Exp.equal e n_lexp1 && in_foot && not (has_fld_hidden fsel) ->
@@ -545,11 +549,10 @@ let execute___release_autorelease_pool
     let call_release res atom =
       match res, atom with
       | ((prop', path') :: _, Sil.Apred (_, exp :: _)) ->
-          (try
+          List.find ~f:(function
-             let hpred = IList.find (function
               | Sil.Hpointsto(e1, _, _) -> Exp.equal e1 exp
-                 | _ -> false) prop_.Prop.sigma in
+              | _ -> false) prop_.Prop.sigma |>
-             match hpred with
+          Option.value_map ~f:(function
               | Sil.Hpointsto (_, _, Exp.Sizeof (typ, _, _)) ->
                   let res1 =
                     execute___objc_release
@@ -559,7 +562,8 @@ let execute___release_autorelease_pool
                         path = path'; } in
                   res1
               | _ -> res
-           with Not_found -> res)
+            )
+            ~default:res
       | _ -> res in
     IList.fold_left call_release [(prop_without_attribute, path)] autoreleased_objects
   else execute___no_op prop_ path
@@ -644,16 +648,21 @@ let execute___objc_cast { Builtin.tenv; pdesc; prop_; path; ret_id; args; }
       let pname = Procdesc.get_proc_name pdesc in
       let val1, prop__ = check_arith_norm_exp tenv pname val1_ prop_ in
       let texp2, prop = check_arith_norm_exp tenv pname texp2_ prop__ in
-      (try
+      (match
-         let hpred = IList.find (function
+         List.find ~f:(function
              | Sil.Hpointsto(e1, _, _) -> Exp.equal e1 val1
-             | _ -> false) prop.Prop.sigma in
+             | _ -> false) prop.Prop.sigma |>
-         match hpred, texp2 with
+         Option.map ~f:(fun hpred -> match hpred, texp2 with
              | Sil.Hpointsto (val1, _, _), Exp.Sizeof _ ->
                  let prop' = replace_ptsto_texp tenv prop val1 texp2 in
                  [(return_result tenv val1 prop' ret_id, path)]
              | _ -> [(return_result tenv val1 prop ret_id, path)]
-       with Not_found -> [(return_result tenv val1 prop ret_id, path)])
+           )
+       with
+       | Some res ->
+           res
+       | None ->
+           [(return_result tenv val1 prop ret_id, path)])
   | _ -> raise (Exceptions.Wrong_argument_number __POS__)
 
 let execute_abort { Builtin.proc_name; }
@@ -720,7 +729,7 @@ let execute_free mk { Builtin.pdesc; instr; tenv; prop_; path; args; loc; }
           Propset.to_proplist (prune tenv ~positive:false n_lexp prop) in
         let plist =
           prop_zero @ (* model: if 0 then skip else _execute_free_nonzero *)
-          IList.flatten (IList.map (fun p ->
+          List.concat (IList.map (fun p ->
               _execute_free_nonzero mk pdesc tenv instr p
                 (Prop.exp_normalize_prop tenv p lexp) typ loc) prop_nonzero) in
         IList.map (fun p -> (p, path)) plist
@@ -792,18 +801,18 @@ let execute___cxx_typeid ({ Builtin.pdesc; tenv; prop_; args; loc} as r)
   | type_info_exp :: rest ->
       (let res = execute_alloc PredSymb.Mnew false { r with args = [type_info_exp] } in
        match rest with
-       | [(field_exp, _); (lexp, typ)] ->
+       | [(field_exp, _); (lexp, typ_)] ->
            let pname = Procdesc.get_proc_name pdesc in
            let n_lexp, prop = check_arith_norm_exp tenv pname lexp prop_ in
            let typ =
-             try
+             List.find ~f:(function
-               let hpred = IList.find (function
                  | Sil.Hpointsto (e, _, _) -> Exp.equal e n_lexp
-                   | _ -> false) prop.Prop.sigma in
+                 | _ -> false) prop.Prop.sigma |>
-               match hpred with
+             Option.value_map ~f:(function
                  | Sil.Hpointsto (_, _, Exp.Sizeof (dynamic_type, _, _)) -> dynamic_type
-               | _ -> typ
+                 | _ -> typ_
-             with Not_found -> typ in
+               )
+               ~default:typ_ in
            let typ_string = Typ.to_string typ in
            let set_instr =
              Sil.Store (field_exp, Typ.Tvoid, Exp.Const (Const.Cstr typ_string), loc) in
@@ -843,7 +852,7 @@ let execute_scan_function skip_n_arguments ({ Builtin.args } as call_args)
   match args with
   | _ when IList.length args >= skip_n_arguments ->
       let varargs = ref args in
-      for _ = 1 to skip_n_arguments do varargs := IList.tl !varargs done;
+      varargs := List.drop !varargs skip_n_arguments;
       SymExec.unknown_or_scan_call
         ~is_scan:true
         None

infer/src/backend/InferAnalyze.re

@@ -54,7 +54,7 @@ let analyze_cluster cluster_num (cluster: Cluster.t) => {
 };
 
 let output_json_makefile_stats clusters => {
-  let clusters_to_analyze = IList.filter ClusterMakefile.cluster_should_be_analyzed clusters;
+  let clusters_to_analyze = List.filter f::ClusterMakefile.cluster_should_be_analyzed clusters;
   let num_files = IList.length clusters_to_analyze;
   let num_procs = 0;
   /* can't compute it at this stage */

infer/src/backend/InferPrint.re

@@ -33,13 +33,13 @@ let load_specfiles () => {
       | Sys_error _ => []
       };
     let all_filepaths = IList.map (fun fname => Filename.concat dir fname) all_filenames;
-    IList.filter is_specs_file all_filepaths
+    List.filter f::is_specs_file all_filepaths
   };
   let specs_dirs = {
     let result_specs_dir = DB.filename_to_string DB.Results_dir.specs_dir;
     [result_specs_dir, ...Config.specs_library]
   };
-  IList.flatten (IList.map specs_files_in_dir specs_dirs)
+  List.concat (IList.map specs_files_in_dir specs_dirs)
 };
 
 
@@ -543,7 +543,8 @@ let pp_tests_of_report fmt report => {
   let pp_trace_elem fmt {description} => F.fprintf fmt "%s" description;
   let pp_trace fmt trace =>
     if Config.print_traces_in_tests {
-      let trace_without_empty_descs = IList.filter (fun {description} => description != "") trace;
+      let trace_without_empty_descs =
+        List.filter f::(fun {description} => description != "") trace;
       F.fprintf fmt ", [%a]" (Pp.comma_seq pp_trace_elem) trace_without_empty_descs
     };
   let pp_row jsonbug =>

infer/src/backend/PropUtil.re

@@ -25,7 +25,7 @@ let get_name_of_objc_static_locals (curr_f: Procdesc.t) p => {
     | _ => []
     };
   let vars_sigma = IList.map hpred_local_static p.Prop.sigma;
-  IList.flatten (IList.flatten vars_sigma)
+  List.concat (List.concat vars_sigma)
 };
 
 /* returns a list of local variables that points to an objc block in a proposition */
@@ -41,7 +41,7 @@ let get_name_of_objc_block_locals p => {
     | _ => []
     };
   let vars_sigma = IList.map hpred_local_blocks p.Prop.sigma;
-  IList.flatten (IList.flatten vars_sigma)
+  List.concat (List.concat vars_sigma)
 };
 
 let remove_abduced_retvars tenv p => {
@@ -101,8 +101,8 @@ let remove_abduced_retvars tenv p => {
         | Exp.BinOp _ e0 e1
         | Exp.Lindex e0 e1 => exp_contains e0 || exp_contains e1
         | _ => false;
-      IList.filter
+      List.filter
-        (
+        f::(
           fun
           | Sil.Aeq lhs rhs
           | Sil.Aneq lhs rhs => exp_contains lhs || exp_contains rhs
@@ -202,6 +202,6 @@ let remove_seed_vars tenv (prop: Prop.t 'a) :Prop.t Prop.normal => {
     | Sil.Hpointsto (Exp.Lvar pv) _ _ => not (Pvar.is_seed pv)
     | _ => true;
   let sigma = prop.sigma;
-  let sigma' = IList.filter hpred_not_seed sigma;
+  let sigma' = List.filter f::hpred_not_seed sigma;
   Prop.normalize tenv (Prop.set prop sigma::sigma')
 };

infer/src/backend/StatsAggregator.re

@@ -33,7 +33,7 @@ let find_json_files_in_dir dir => {
     {
       let content = Array.to_list (Sys.readdir dir);
       let content_with_path = IList.map (fun p => Filename.concat dir p) content;
-      IList.filter is_valid_json_file content_with_path
+      List.filter f::is_valid_json_file content_with_path
     } :
     []
 };

infer/src/backend/abs.ml

@@ -71,13 +71,13 @@ let create_condition_ls ids_private id_base p_leftover (inst: Sil.subst) =
     let inst_of_base = try Sil.sub_find (Ident.equal id_base) inst_public with Not_found -> assert false in
     let insts_of_private_ids = Sil.sub_range inst_private in
     (insts_of_private_ids, insts_of_public_ids, inst_of_base) in
-  let fav_insts_of_public_ids = IList.flatten (IList.map Sil.exp_fav_list insts_of_public_ids) in
+  let fav_insts_of_public_ids = List.concat (IList.map Sil.exp_fav_list insts_of_public_ids) in
-  let fav_insts_of_private_ids = IList.flatten (IList.map Sil.exp_fav_list insts_of_private_ids) in
+  let fav_insts_of_private_ids = List.concat (IList.map Sil.exp_fav_list insts_of_private_ids) in
   let (fav_p_leftover, _) =
     let sigma = p_leftover.Prop.sigma in
     (sigma_fav_list sigma, sigma_fav_in_pvars_list sigma) in
   let fpv_inst_of_base = Sil.exp_fpv inst_of_base in
-  let fpv_insts_of_private_ids = IList.flatten (IList.map Sil.exp_fpv insts_of_private_ids) in
+  let fpv_insts_of_private_ids = List.concat (IList.map Sil.exp_fpv insts_of_private_ids) in
   (*
   let fav_inst_of_base = Sil.exp_fav_list inst_of_base in
   L.out "@[.... application of condition ....@\n@.";
@@ -420,7 +420,7 @@ let typ_get_recursive_flds tenv typ_exp =
       match typ with
       | Tstruct name -> (
           match Tenv.lookup tenv name with
-          | Some { fields } -> IList.map fst3 (IList.filter (filter typ) fields)
+          | Some { fields } -> IList.map fst3 (List.filter ~f:(filter typ) fields)
           | None ->
               L.err "@.typ_get_recursive: unexpected type expr: %a@." Exp.pp typ_exp;
               [] (* ToDo: assert false *)
@@ -473,7 +473,7 @@ let discover_para_candidates tenv p =
     match se with
     | Sil.Eexp _ | Sil.Earray _ -> ()
     | Sil.Estruct (fsel, _) ->
-        let fsel' = IList.filter (fun (fld, _) -> is_rec_fld fld) fsel in
+        let fsel' = List.filter ~f:(fun (fld, _) -> is_rec_fld fld) fsel in
         let process (_, nextse) =
           match nextse with
           | Sil.Eexp (next, _) -> add_edge (root, next)
@@ -491,7 +491,7 @@ let discover_para_candidates tenv p =
     | [] -> IList.rev found
     | (e1, e2) :: edges_notseen ->
         let edges_others = (IList.rev edges_seen) @ edges_notseen in
-        let edges_matched = IList.filter (fun (e1', _) -> Exp.equal e2 e1') edges_others in
+        let edges_matched = List.filter ~f:(fun (e1', _) -> Exp.equal e2 e1') edges_others in
         let new_found =
           let f found_acc (_, e3) = (e1, e2, e3) :: found_acc in
           IList.fold_left f found edges_matched in
@@ -509,7 +509,7 @@ let discover_para_dll_candidates tenv p =
     match se with
     | Sil.Eexp _ | Sil.Earray _ -> ()
     | Sil.Estruct (fsel, _) ->
-        let fsel' = IList.filter (fun (fld, _) -> is_rec_fld fld) fsel in
+        let fsel' = List.filter ~f:(fun (fld, _) -> is_rec_fld fld) fsel in
         let convert_to_exp acc (_, se) =
           match se with
           | Sil.Eexp (e, _) -> e:: acc
@@ -531,7 +531,7 @@ let discover_para_dll_candidates tenv p =
     | [] -> IList.rev found
     | (iF, blink, flink) :: edges_notseen ->
         let edges_others = (IList.rev edges_seen) @ edges_notseen in
-        let edges_matched = IList.filter (fun (e1', _, _) -> Exp.equal flink e1') edges_others in
+        let edges_matched = List.filter ~f:(fun (e1', _, _) -> Exp.equal flink e1') edges_others in
         let new_found =
           let f found_acc (_, _, flink2) = (iF, blink, flink, flink2) :: found_acc in
           IList.fold_left f found edges_matched in
@@ -627,7 +627,7 @@ let eqs_solve ids_in eqs_in =
     let sub_dom = IList.map fst sub_list in
     let filter id =
       not (List.exists ~f:(fun id' -> Ident.equal id id') sub_dom) in
-    IList.filter filter ids_in in
+    List.filter ~f:filter ids_in in
   match solve Sil.sub_empty eqs_in with
   | None -> None
   | Some sub -> Some (compute_ids sub, sub)
@@ -703,8 +703,8 @@ let abs_rules_apply_lists tenv (p_in: Prop.normal Prop.t) : Prop.normal Prop.t =
     let (closed_paras_sll, closed_paras_dll) =
       let paras_sll = discover_para tenv p in
       let paras_dll = discover_para_dll tenv p in
-      let closed_paras_sll = IList.flatten (IList.map hpara_special_cases paras_sll) in
+      let closed_paras_sll = List.concat (IList.map hpara_special_cases paras_sll) in
-      let closed_paras_dll = IList.flatten (IList.map hpara_special_cases_dll paras_dll) in
+      let closed_paras_dll = List.concat (IList.map hpara_special_cases_dll paras_dll) in
       begin
         (*
         if IList.length closed_paras_sll >= 1 then
@@ -733,8 +733,8 @@ let abs_rules_apply_lists tenv (p_in: Prop.normal Prop.t) : Prop.normal Prop.t =
       let filter_dll para =
         not (List.exists ~f:(eq_dll para) old_rsets) &&
         not (List.exists ~f:(eq_dll para) !new_rsets) in
-      let todo_paras_sll = IList.filter filter_sll closed_paras_sll in
+      let todo_paras_sll = List.filter ~f:filter_sll closed_paras_sll in
-      let todo_paras_dll = IList.filter filter_dll closed_paras_dll in
+      let todo_paras_dll = List.filter ~f:filter_dll closed_paras_dll in
       (todo_paras_sll, todo_paras_dll) in
     let f_recurse () =
       let todo_rsets_sll =
@@ -771,7 +771,7 @@ let abstract_pure_part tenv p ~(from_abstract_footprint: bool) =
             if Ident.is_primed id then Sil.fav_mem fav_sigma id
             else if Ident.is_footprint id then Sil.fav_mem fav_nonpure id
             else true) in
-      IList.filter filter pure in
+      List.filter ~f:filter pure in
     let new_pure =
       IList.fold_left
         (fun pi a ->
@@ -825,7 +825,7 @@ let abstract_gc tenv p =
         Sil.fav_is_empty fav_a
         ||
         IList.intersect Ident.compare (Sil.fav_to_list fav_a) (Sil.fav_to_list fav_p_without_pi) in
-  let new_pi = IList.filter strong_filter pi in
+  let new_pi = List.filter ~f:strong_filter pi in
   let prop = Prop.normalize tenv (Prop.set p ~pi:new_pi) in
   match Prop.prop_iter_create prop with
   | None -> prop
@@ -882,11 +882,11 @@ let get_cycle root prop =
   let get_points_to e =
     match e with
     | Sil.Eexp(e', _) ->
-        (try
+        List.find
-           Some(IList.find (fun hpred -> match hpred with
+          ~f:(fun hpred -> match hpred with
-               | Sil.Hpointsto(e'', _, _) -> Exp.equal e'' e'
+              | Sil.Hpointsto (e'', _, _) -> Exp.equal e'' e'
-               | _ -> false) sigma)
+              | _ -> false)
-         with _ -> None)
+          sigma
     | _ -> None in
   let print_cycle cyc =
     (L.d_str "Cycle= ";
@@ -962,10 +962,8 @@ let get_var_retain_cycle prop_ =
       when Exp.equal e e' && Typ.is_block_type typ -> true
     | _, _ -> false in
   let find v =
-    try
+    List.find ~f:(is_pvar v) sigma |>
-      let hp = IList.find (is_pvar v) sigma in
+    Option.map ~f:Sil.hpred_get_lhs in
-      Some (Sil.hpred_get_lhs hp)
-    with Not_found -> None in
   let find_block v =
     if (List.exists ~f:(is_hpred_block v) sigma) then
       Some (Exp.Lvar Sil.block_pvar)
@@ -987,7 +985,7 @@ let get_var_retain_cycle prop_ =
     | hp:: sigma' ->
         let cycle = get_cycle hp prop_ in
         L.d_strln "Filtering pvar in cycle ";
-        let cycle' = IList.flatten (IList.map find_or_block cycle) in
+        let cycle' = List.concat (IList.map find_or_block cycle) in
         if List.is_empty cycle' then do_sigma sigma'
         else cycle' in
   do_sigma sigma
@@ -1007,8 +1005,8 @@ let cycle_has_weak_or_unretained_or_assign_field tenv cycle =
         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))
+            List.find ~f:equal_fn (fields @ statics) |>
-            with Not_found -> []
+            Option.value_map ~f:trd3 ~default:[]
           )
         | None -> []
       )
@@ -1241,9 +1239,9 @@ let get_local_stack cur_sigma init_sigma =
   let filter_local_stack olds = function
     | Sil.Hpointsto (Exp.Lvar pvar, _, _) -> not (List.exists ~f:(Pvar.equal pvar) olds)
     | Sil.Hpointsto _ | Sil.Hlseg _ | Sil.Hdllseg _ -> false in
-  let init_stack = IList.filter filter_stack init_sigma in
+  let init_stack = List.filter ~f:filter_stack init_sigma in
   let init_stack_pvars = IList.map get_stack_var init_stack in
-  let cur_local_stack = IList.filter (filter_local_stack init_stack_pvars) cur_sigma in
+  let cur_local_stack = List.filter ~f:(filter_local_stack init_stack_pvars) cur_sigma in
   let cur_local_stack_pvars = IList.map get_stack_var cur_local_stack in
   (cur_local_stack, cur_local_stack_pvars)
 
@@ -1261,7 +1259,7 @@ let remove_local_stack sigma pvars =
   let filter_non_stack = function
     | Sil.Hpointsto (Exp.Lvar pvar, _, _) -> not (List.exists ~f:(Pvar.equal pvar) pvars)
     | Sil.Hpointsto _ | Sil.Hlseg _ | Sil.Hdllseg _ -> true in
-  IList.filter filter_non_stack sigma
+  List.filter ~f:filter_non_stack sigma
 
 (** [prop_set_fooprint p p_foot] removes a local stack from [p_foot],
     and sets proposition [p_foot] as footprint of [p]. *)

infer/src/backend/absarray.ml

@@ -76,14 +76,16 @@ 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.equal_fieldname f' fld) fsel) in
+            let se' =
-            let t' = snd3 (IList.find (fun (f', _, _) -> Ident.equal_fieldname f' fld) fields) in
+              snd (List.find_exn ~f:(fun (f', _) -> Ident.equal_fieldname f' fld) fsel) in
+            let t' =
+              snd3 (List.find_exn ~f:(fun (f', _, _) -> Ident.equal_fieldname f' fld) fields) in
             get_strexp_at_syn_offsets tenv se' t' syn_offs'
         | None ->
             fail ()
       )
     | Sil.Earray (_, esel, _), Typ.Tarray (t', _), Index ind :: syn_offs' ->
-        let se' = snd (IList.find (fun (i', _) -> Exp.equal i' ind) esel) in
+        let se' = snd (List.find_exn ~f:(fun (i', _) -> Exp.equal i' ind) esel) in
         get_strexp_at_syn_offsets tenv se' t' syn_offs'
     | _ ->
         fail ()
@@ -96,9 +98,9 @@ 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.equal_fieldname f' fld) fsel) in
+            let se' = snd (List.find_exn ~f:(fun (f', _) -> Ident.equal_fieldname f' fld) fsel) in
             let t' = (fun (_,y,_) -> y)
-                (IList.find (fun (f', _, _) ->
+                (List.find_exn ~f:(fun (f', _, _) ->
                      Ident.equal_fieldname f' fld) fields) in
             let se_mod = replace_strexp_at_syn_offsets tenv se' t' syn_offs' update in
             let fsel' =
@@ -110,7 +112,7 @@ end = struct
             assert false
       )
     | Sil.Earray (len, esel, inst), Tarray (t', _), Index idx :: syn_offs' ->
-        let se' = snd (IList.find (fun (i', _) -> Exp.equal i' idx) esel) in
+        let se' = snd (List.find_exn ~f:(fun (i', _) -> Exp.equal i' idx) esel) in
         let se_mod = replace_strexp_at_syn_offsets tenv se' t' syn_offs' update in
         let esel' =
           IList.map (fun ese -> if Exp.equal (fst ese) idx then (idx, se_mod) else ese) esel in
@@ -150,7 +152,7 @@ end = struct
     let filter = function
       | Sil.Hpointsto (e, _, _) -> Exp.equal root e
       | _ -> false in
-    let hpred = IList.find filter sigma in
+    let hpred = List.find_exn ~f:filter sigma in
     (sigma, hpred, syn_offs)
 
   (** Find a sub strexp with the given property. Can raise [Not_found] *)
@@ -177,11 +179,12 @@ end = struct
       | [] -> ()
       | (f, se) :: fsel' ->
           begin
-            try
+            match List.find ~f:(fun (f', _, _) -> Ident.equal_fieldname f' f) ftal with
-              let t = snd3 (IList.find (fun (f', _, _) -> Ident.equal_fieldname f' f) ftal) in
+            | Some (_, t, _) ->
                 find_offset_sexp sigma_other hpred root ((Field (f, typ)) :: offs) se t
-            with Not_found ->
+            | None ->
-              L.d_strln ("Can't find field " ^ (Ident.fieldname_to_string f) ^ " in StrexpMatch.find")
+                L.d_strln
+                  ("Can't find field " ^ (Ident.fieldname_to_string f) ^ " in StrexpMatch.find")
           end;
           find_offset_fsel sigma_other hpred root offs fsel' ftal typ
     and find_offset_esel sigma_other hpred root offs esel t = match esel with
@@ -261,18 +264,6 @@ end = struct
       | _ -> assert false in
     let hpred' = hpred_replace_strexp tenv footprint_part hpred syn_offs update in
     replace_hpred (sigma, hpred, syn_offs) hpred'
-(*
-  (** Get the partition of the sigma: the unmatched part of the sigma and the matched hpred *)
-  let get_sigma_partition (sigma, hpred, _) =
-    let sigma_unmatched = IList.filter (fun hpred' -> not (hpred' == hpred)) sigma in
-    (sigma_unmatched, hpred)
-
-  (** Replace the strexp and the unmatched part of the sigma by the given inputs *)
-  let replace_strexp_sigma footprint_part ((_, hpred, syn_offs) : t) se_in sigma_in =
-    let new_sigma = hpred :: sigma_in in
-    let sigma' = replace_strexp tenv footprint_part (new_sigma, hpred, syn_offs) se_in in
-    IList.sort Sil.compare_hpred sigma'
-*)
 end
 
 (** This function renames expressions in [p]. The renaming is, roughly
@@ -292,10 +283,9 @@ let prop_replace_path_index tenv
           ) acc_outer map
       ) [] elist_path in
   let expmap_fun e' =
-    try
+    Option.value_map
-      let _, fresh_e = IList.find (fun (e, _) -> Exp.equal e e') expmap_list in
+      ~f:snd (List.find ~f:(fun (e, _) -> Exp.equal e e') expmap_list)
-      fresh_e
+      ~default:e' in
-    with Not_found -> e' in
   Prop.prop_expmap expmap_fun p
 
 (** This function uses [update] and transforms the two sigma parts of [p],
@@ -376,7 +366,7 @@ let index_is_pointed_to tenv (p: Prop.normal Prop.t) (path: StrexpMatch.path) (i
     let elist_path = StrexpMatch.path_to_exps path in
     let add_index i e = Prop.exp_normalize_prop tenv p (Exp.Lindex(e, i)) in
     fun i -> IList.map (add_index i) elist_path in
-  let pointers = IList.flatten (IList.map add_index_to_paths indices) in
+  let pointers = List.concat (IList.map add_index_to_paths indices) in
   let filter = function
     | Sil.Hpointsto (_, Sil.Eexp (e, _), _) -> List.exists ~f:(Exp.equal e) pointers
     | _ -> false in
@@ -502,7 +492,7 @@ let strexp_do_abstract tenv
     let default_indices =
       match IList.map fst esel with
       | [] -> []
-      | indices -> [IList.hd (IList.rev indices)] (* keep last key at least *) in
+      | indices -> [List.hd_exn (IList.rev indices)] (* keep last key at least *) in
     partition_abstract should_keep abstract esel default_indices in
   let do_footprint () =
     match se_in with
@@ -510,7 +500,7 @@ let strexp_do_abstract tenv
     | _ -> assert false in
 
   let filter_abstract d_keys should_keep abstract ksel default_keys =
-    let keep_ksel = IList.filter should_keep ksel in
+    let keep_ksel = List.filter ~f:should_keep ksel in
     let keep_keys = IList.map fst keep_ksel in
     let keep_keys' = if List.is_empty keep_keys then default_keys else keep_keys in
     if Config.trace_absarray then (L.d_str "keep "; d_keys keep_keys'; L.d_ln ());
@@ -593,7 +583,7 @@ let remove_redundant_elements tenv prop =
     Sil.fav_duplicates := false;
     (* L.d_str "favl_curr "; IList.iter (fun id -> Sil.d_exp (Exp.Var id)) favl_curr; L.d_ln();
        L.d_str "favl_foot "; IList.iter (fun id -> Sil.d_exp (Exp.Var id)) favl_foot; L.d_ln(); *)
-    let num_occur l id = IList.length (IList.filter (fun id' -> Ident.equal id id') l) in
+    let num_occur l id = IList.length (List.filter ~f:(fun id' -> Ident.equal id id') l) in
     let at_most_once v =
       num_occur favl_curr v <= 1 && num_occur favl_foot v <= 1 in
     at_most_once in
@@ -613,7 +603,7 @@ let remove_redundant_elements tenv prop =
     | _ -> true in
   let remove_redundant_se fp_part = function
     | Sil.Earray (len, esel, inst) ->
-        let esel' = IList.filter (filter_redundant_e_se fp_part) esel in
+        let esel' = List.filter ~f:(filter_redundant_e_se fp_part) esel in
         Sil.Earray (len, esel', inst)
     | se -> se in
   let remove_redundant_hpred fp_part = function

infer/src/backend/callbacks.ml

@@ -122,7 +122,7 @@ let iterate_cluster_callbacks all_procs exe_env proc_names =
   (* Procedures matching the given language or all if no language is specified. *)
   let relevant_procedures language_opt =
     Option.value_map
-      ~f:(fun l -> IList.filter (fun p -> Config.equal_language l (get_language p)) proc_names)
+      ~f:(fun l -> List.filter ~f:(fun p -> Config.equal_language l (get_language p)) proc_names)
       ~default:proc_names
       language_opt in
 

infer/src/backend/crashcontext.ml

@@ -23,7 +23,7 @@ let frame_id_of_stackframe frame =
     loc_str
 
 let frame_id_of_summary stacktree =
-  let short_name = IList.hd
+  let short_name = List.hd_exn
       (Str.split (Str.regexp "(") stacktree.Stacktree_j.method_name) in
   match stacktree.Stacktree_j.location with
   | None ->

infer/src/backend/dom.ml

@@ -450,10 +450,13 @@ end = struct
     if n1 <> 0 then n1 else Exp.compare e2 e2'
 
   let get_fresh_exp e1 e2 =
-    try
+    match
-      let (_, _, e) = IList.find (fun (e1', e2', _) -> Exp.equal e1 e1' && Exp.equal e2 e2') !t in
+      List.find ~f:(fun (e1', e2', _) -> Exp.equal e1 e1' && Exp.equal e2 e2') !t |>
-      e
+      Option.map ~f:trd3
-    with Not_found ->
+    with
+    | Some res ->
+        res
+    | None ->
         let e = Exp.get_undefined (JoinState.get_footprint ()) in
         t := (e1, e2, e)::!t;
         e
@@ -478,14 +481,19 @@ end = struct
     let rec f_eqs_entry ((e1, e2, e) as entry) eqs_acc t_seen = function
       | [] -> eqs_acc, t_seen
       | ((e1', e2', e') as entry'):: t_rest' ->
-          try
+          (match
-            let n = IList.find (fun n -> add_and_chk_eq e1 e1' n && add_and_chk_eq e2 e2' n) minus2_to_2 in
+             List.find ~f:(fun n ->
+                 add_and_chk_eq e1 e1' n && add_and_chk_eq e2 e2' n) minus2_to_2 |>
+             Option.map ~f:(fun n ->
                  let eq = add_and_gen_eq e e' n in
                  let eqs_acc' = eq:: eqs_acc in
-            f_eqs_entry entry eqs_acc' t_seen t_rest'
+                 f_eqs_entry entry eqs_acc' t_seen t_rest')
-          with Not_found ->
+           with
+           | Some res ->
+               res
+           | None ->
                let t_seen' = entry':: t_seen in
-            f_eqs_entry entry eqs_acc t_seen' t_rest' in
+               f_eqs_entry entry eqs_acc t_seen' t_rest') in
     let rec f_eqs eqs_acc t_acc = function
       | [] -> (eqs_acc, t_acc)
       | entry:: t_rest ->
@@ -505,15 +513,6 @@ end = struct
       | _ -> acc in
     IList.fold_left f_ineqs eqs t_minimal
 
-(*
-  let lookup side e =
-    try
-      let (e1, e2, e) =
-        IList.find (fun (e1', e2', _) -> Exp.equal e (select side e1' e2')) !t in
-      Some (e, select (opposite side) e1 e2)
-    with Not_found ->
-      None
-*)
 end
 
 (** {2 Modules for renaming} *)
@@ -556,7 +555,7 @@ end = struct
           (Ident.is_footprint id) &&
           (Sil.fav_for_all (Sil.exp_fav e) (fun id -> not (Ident.is_primed id)))
       | _ -> false in
-    let t' = IList.filter f !tbl in
+    let t' = List.filter ~f !tbl in
     tbl := t';
     t'
 
@@ -571,7 +570,7 @@ end = struct
         | Exp.Lvar _ | Exp.Var _
         | Exp.BinOp (Binop.PlusA, Exp.Var _, _) ->
             let is_same_e (e1, e2, _) = Exp.equal e (select side e1 e2) in
-            let assoc = IList.filter is_same_e !tbl in
+            let assoc = List.filter ~f:is_same_e !tbl in
             IList.map (fun (e1, e2, _) -> select side_op e1 e2) assoc
         | _ ->
             L.d_str "no pattern match in check lost_little e: "; Sil.d_exp e; L.d_ln ();
@@ -583,7 +582,7 @@ end = struct
 
   let lookup_side' side e =
     let f (e1, e2, _) = Exp.equal e (select side e1 e2) in
-    IList.filter f !tbl
+    List.filter ~f !tbl
 
   let lookup_side_induced' side e =
     let res = ref [] in
@@ -624,7 +623,7 @@ end = struct
 
   let to_subst_proj (side: side) vars =
     let renaming_restricted =
-      IList.filter (function (_, _, Exp.Var i) -> Sil.fav_mem vars i | _ -> assert false) !tbl in
+      List.filter ~f:(function (_, _, Exp.Var i) -> Sil.fav_mem vars i | _ -> assert false) !tbl in
     let sub_list_side =
       IList.map
         (function (e1, e2, Exp.Var i) -> (i, select side e1 e2) | _ -> assert false)
@@ -644,7 +643,7 @@ end = struct
         match select side e1 e2 with
         | Exp.Var i -> can_rename i
         | _ -> false in
-      IList.filter pick_id_case !tbl in
+      List.filter ~f:pick_id_case !tbl in
     let sub_list =
       let project (e1, e2, e) =
         match select side e1 e2 with
@@ -747,16 +746,19 @@ end = struct
   (* Extend the renaming relation. At least one of e1 and e2
    * should be a primed or footprint variable *)
   let extend e1 e2 default_op =
-    try
+    match
-      let eq_to_e (f1, f2, _) = Exp.equal e1 f1 && Exp.equal e2 f2 in
+      List.find ~f:(fun (f1, f2, _) -> Exp.equal e1 f1 && Exp.equal e2 f2) !tbl |>
-      let _, _, res = IList.find eq_to_e !tbl in
+      Option.map ~f:trd3
+    with
+    | Some res ->
         res
-    with Not_found ->
+    | None ->
         let fav1 = Sil.exp_fav e1 in
         let fav2 = Sil.exp_fav e2 in
         let no_ren1 = not (Sil.fav_exists fav1 can_rename) in
         let no_ren2 = not (Sil.fav_exists fav2 can_rename) in
-      let some_primed () = Sil.fav_exists fav1 Ident.is_primed || Sil.fav_exists fav2 Ident.is_primed in
+        let some_primed () =
+          Sil.fav_exists fav1 Ident.is_primed || Sil.fav_exists fav2 Ident.is_primed in
         let e =
           if (no_ren1 && no_ren2) then
             if (Exp.equal e1 e2) then e1 else (L.d_strln "failure reason 13"; raise IList.Fail)
@@ -764,24 +766,15 @@ end = struct
             match default_op with
             | ExtDefault e -> e
             | ExtFresh ->
-              let kind = if JoinState.get_footprint () && not (some_primed ()) then Ident.kfootprint else Ident.kprimed in
+                let kind =
+                  if JoinState.get_footprint () && not (some_primed ())
+                  then Ident.kfootprint
+                  else Ident.kprimed in
                 Exp.Var (Ident.create_fresh kind) in
         let entry = e1, e2, e in
         push entry;
         Todo.push entry;
         e
-(*
-  let get e1 e2 =
-    let f (e1', e2', _) = Exp.equal e1 e1' && Exp.equal e2 e2' in
-    match (IList.filter f !tbl) with
-    | [] -> None
-    | (_, _, e):: _ -> Some e
-
-  let pp pe f renaming =
-    let pp_triple f (e1, e2, e3) =
-      F.fprintf f "(%a,%a,%a)" (Sil.pp_exp pe) e3 (Sil.pp_exp pe) e1 (Sil.pp_exp pe) e2 in
-    (pp_seq pp_triple) f renaming
-*)
 end
 
 (** {2 Functions for constructing fresh sil data types} *)
@@ -1821,7 +1814,7 @@ let footprint_partial_join' tenv (p1: Prop.normal Prop.t) (p2: Prop.normal Prop.
     let pi_fp =
       let pi_fp0 = Prop.get_pure efp in
       let f a = Sil.fav_for_all (Sil.atom_fav a) Ident.is_footprint in
-      IList.filter f pi_fp0 in
+      List.filter ~f pi_fp0 in
     let sigma_fp =
       let sigma_fp0 = efp.Prop.sigma in
       let f a = Sil.fav_exists (Sil.hpred_fav a) (fun a -> not (Ident.is_footprint a)) in

infer/src/backend/dotty.ml

@@ -289,7 +289,7 @@ let make_dangling_boxes pe allocated_nodes (sigma_lambda: (Sil.hpred * int) list
     | d:: candidates ->
         if (is_allocated d) then subtract_allocated candidates
         else d:: subtract_allocated candidates in
-  let candidate_dangling = IList.flatten (IList.map get_rhs_predicate sigma_lambda) in
+  let candidate_dangling = List.concat (IList.map get_rhs_predicate sigma_lambda) in
   let candidate_dangling = filter_duplicate candidate_dangling [] in
   let dangling = subtract_allocated candidate_dangling in
   dangling_dotboxes:= dangling
@@ -338,7 +338,7 @@ let set_exps_neq_zero pi =
   IList.iter f pi
 
 let box_dangling e =
-  let entry_e = IList.filter (fun b -> match b with
+  let entry_e = List.filter ~f:(fun b -> match b with
       | Dotdangling(_, e', _) -> Exp.equal e e' | _ -> false ) !dangling_dotboxes in
   match entry_e with
   |[] -> None
@@ -477,7 +477,7 @@ let compute_target_from_eexp dotnodes e p lambda =
     [(LinkExpToExp, n', "")]
   else
     let nodes_e = select_nodes_exp_lambda dotnodes e lambda in
-    let nodes_e_no_struct = IList.filter is_not_struct nodes_e in
+    let nodes_e_no_struct = List.filter ~f:is_not_struct nodes_e in
     let trg = IList.map get_coordinate_id nodes_e_no_struct in
     (match trg with
      | [] ->
@@ -498,7 +498,7 @@ let rec dotty_mk_set_links dotnodes sigma p f cycle =
         let target_list = compute_target_array_elements dotnodes lie p f lambda in
         (* below it's n+1 because n is the address, n+1 is the actual array node*)
         let ff n = IList.map (fun (k, lab_src, m, lab_trg) -> mk_link k (mk_coordinate (n + 1) lambda) (strip_special_chars lab_src) (mk_coordinate m lambda) (strip_special_chars lab_trg)) target_list in
-        let links_from_elements = IList.flatten (IList.map ff (n:: nl)) in
+        let links_from_elements = List.concat (IList.map ff (n:: nl)) in
 
         let trg_label = strip_special_chars (Exp.to_string e) in
         let lnk = mk_link (LinkToArray) (mk_coordinate n lambda) "" (mk_coordinate (n + 1) lambda) trg_label in
@@ -519,11 +519,11 @@ let rec dotty_mk_set_links dotnodes sigma p f cycle =
              ) target_list in
            let nodes_e = select_nodes_exp_lambda dotnodes e lambda in
            let address_struct_id =
-             try get_coordinate_id (IList.hd (IList.filter (is_source_node_of_exp e) nodes_e))
+             try get_coordinate_id (List.hd_exn (List.filter ~f:(is_source_node_of_exp e) nodes_e))
              with exn when SymOp.exn_not_failure exn -> assert false in
            (* we need to exclude the address node from the sorce of fields. no fields should start from there*)
-           let nl'= IList.filter (fun id -> address_struct_id <> id) nl in
+           let nl'= List.filter ~f:(fun id -> address_struct_id <> id) nl in
-           let links_from_fields = IList.flatten (IList.map ff nl') in
+           let links_from_fields = List.concat (IList.map ff nl') in
            let lnk_from_address_struct = if !print_full_prop then
                let trg_label = strip_special_chars (Exp.to_string e) in
                [mk_link (LinkExpToStruct) (mk_coordinate address_struct_id lambda) ""
@@ -541,7 +541,7 @@ let rec dotty_mk_set_links dotnodes sigma p f cycle =
                  mk_link k (mk_coordinate n lambda) ""
                    (mk_coordinate m lambda) (strip_special_chars lab_target)
                ) target_list in
-             let ll = IList.flatten (IList.map ff nl) in
+             let ll = List.concat (IList.map ff nl) in
              ll @ dotty_mk_set_links dotnodes sigma' p f cycle
            else dotty_mk_set_links dotnodes sigma' p f cycle)
 
@@ -550,7 +550,7 @@ let rec dotty_mk_set_links dotnodes sigma p f cycle =
       (match src with
        | [] -> assert false
        | n:: _ ->
-           let (_, m, lab) = IList.hd (compute_target_from_eexp dotnodes e2 p lambda) in
+           let (_, m, lab) = List.hd_exn (compute_target_from_eexp dotnodes e2 p lambda) in
            let lnk = mk_link LinkToSSL (mk_coordinate (n + 1) lambda) "" (mk_coordinate m lambda) lab in
            lnk:: dotty_mk_set_links dotnodes sigma' p f cycle
       )
@@ -635,11 +635,11 @@ let filter_useless_spec_dollar_box (nodes: dotty_node list) (links: link list) =
   let tmp_nodes = ref nodes in
   let tmp_links = ref links in
   let remove_links_from ln =
-    IList.filter
+    List.filter
-      (fun n' -> not (List.mem ~equal:equal_link ln n'))
+      ~f:(fun n' -> not (List.mem ~equal:equal_link ln n'))
       !tmp_links in
   let remove_node n ns =
-    IList.filter (fun n' -> match n' with
+    List.filter ~f:(fun n' -> match n' with
         | Dotpointsto _ -> (get_coordinate_id n') <> (get_coordinate_id n)
         | _ -> true
       ) ns in
@@ -774,7 +774,7 @@ and dotty_pp_state f pe cycle dotnode =
   | Dotpointsto(coo, e1, c) when !print_full_prop -> dotty_exp coo e1 c false
   | Dotstruct(coo, e1, l, c,te) ->
       let l' = if !print_full_prop then l
-        else IList.filter (fun edge -> in_cycle cycle edge) l in
+        else List.filter ~f:(fun edge -> in_cycle cycle edge) l in
       print_struct f pe e1 te l' coo c
   | Dotarray(coo, e1, e2, l, _, c) when !print_full_prop -> print_array f pe e1 e2 l coo c
   | Dotlseg(coo, e1, _, Sil.Lseg_NE, nesting, _) when !print_full_prop ->
@@ -1119,7 +1119,7 @@ let atom_to_xml_string a =
 
 (* return the dangling node corresponding to an expression it exists or None *)
 let exp_dangling_node e =
-  let entry_e = IList.filter (fun b -> match b with
+  let entry_e = List.filter ~f:(fun b -> match b with
       | VH_dangling(_, e') -> Exp.equal e e' | _ -> false ) !set_dangling_nodes in
   match entry_e with
   |[] -> None
@@ -1202,10 +1202,10 @@ let make_set_dangling_nodes allocated_nodes (sigma: Sil.hpred list) =
     | e:: l' ->
         if (List.exists ~f:(Exp.equal e) seen_exp) then filter_duplicate l' seen_exp
         else e:: filter_duplicate l' (e:: seen_exp) in
-  let rhs_exp_list = IList.flatten (IList.map get_rhs_predicate sigma) in
+  let rhs_exp_list = List.concat (IList.map get_rhs_predicate sigma) in
   let candidate_dangling_exps = filter_duplicate rhs_exp_list [] in
   (* get rid of allocated ones*)
-  let dangling_exps = IList.filter is_not_allocated candidate_dangling_exps in
+  let dangling_exps = List.filter ~f:is_not_allocated candidate_dangling_exps in
   IList.map make_new_dangling dangling_exps
 
 (* return a list of pairs (n,field_lab) where n is a target node*)
@@ -1287,8 +1287,8 @@ let prop_to_set_of_visual_heaps prop =
   incr global_node_counter;
   while (!working_list <> []) do
     set_dangling_nodes:=[];
-    let (n, h) = IList.hd !working_list in
+    let (n, h) = List.hd_exn !working_list in
-    working_list:= IList.tl !working_list;
+    working_list:= List.tl_exn !working_list;
     let nodes = make_visual_heap_nodes h in
     set_dangling_nodes:= make_set_dangling_nodes nodes h;
     let edges = make_visual_heap_edges nodes h prop in

infer/src/backend/errdesc.ml

@@ -78,9 +78,9 @@ let find_in_node_or_preds start_node f_node_instr =
       begin
         visited := Procdesc.NodeSet.add node !visited;
         let instrs = Procdesc.Node.get_instrs node in
-        match IList.find_map_opt (f_node_instr node) (IList.rev instrs) with
+        match List.find_map ~f:(f_node_instr node) (IList.rev instrs) with
         | Some res -> Some res
-        | None -> IList.find_map_opt find (Procdesc.Node.get_preds node)
+        | None -> List.find_map ~f:find (Procdesc.Node.get_preds node)
       end in
   find start_node
 
@@ -537,9 +537,9 @@ let explain_leak tenv hpred prop alloc_att_opt bucket =
                  Pvar.d pvar; L.d_ln ());
               [pvar]
           | _ -> [] in
-        let nullify_pvars = IList.flatten (IList.map get_nullify node_instrs) in
+        let nullify_pvars = List.concat (IList.map get_nullify node_instrs) in
         let nullify_pvars_notmp =
-          IList.filter (fun pvar -> not (Pvar.is_frontend_tmp pvar)) nullify_pvars in
+          List.filter ~f:(fun pvar -> not (Pvar.is_frontend_tmp pvar)) nullify_pvars in
         value_str_from_pvars_vpath nullify_pvars_notmp vpath
     | Some (Sil.Store (lexp, _, _, _)) when is_none vpath ->
         if verbose
@@ -581,11 +581,9 @@ let vpath_find tenv prop _exp : DExp.t option * Typ.t option =
                let typo = match texp with
                  | Exp.Sizeof (Tstruct name, _, _) -> (
                      match Tenv.lookup tenv name with
-                     | Some {fields} -> (
+                     | Some {fields} ->
-                         match IList.find (fun (f', _, _) -> Ident.equal_fieldname f' f) fields with
+                         List.find ~f:(fun (f', _, _) -> Ident.equal_fieldname f' f) fields |>
-                         | _, t, _ -> Some t
+                         Option.map ~f:snd3
-                         | exception Not_found -> None
-                       )
                      | _ ->
                          None
                    )

infer/src/backend/infer.ml

@@ -225,7 +225,7 @@ let capture = function
               ["--java-jar-compiler"; p]) @
           (match IList.rev Config.buck_build_args with
            | args when in_buck_mode ->
-               IList.map (fun arg -> ["--Xbuck"; "'" ^ arg ^ "'"]) args |> IList.flatten
+               IList.map (fun arg -> ["--Xbuck"; "'" ^ arg ^ "'"]) args |> List.concat
            | _ -> []) @
           (if not Config.debug_mode then [] else
              ["--debug"]) @

infer/src/backend/interproc.ml

@@ -394,8 +394,8 @@ let check_assignement_guard pdesc node =
   let is_prune_exp e =
     let prune_var n =
       let ins = Procdesc.Node.get_instrs n in
-      let pi = IList.filter is_prune_instr ins in
+      let pi = List.filter ~f:is_prune_instr ins in
-      let leti = IList.filter is_load_instr ins in
+      let leti = List.filter ~f:is_load_instr ins in
       match pi, leti with
       | [Sil.Prune (Exp.Var (e1), _, _, _)], [Sil.Load (e2, e', _, _)]
       | [Sil.Prune (Exp.UnOp (Unop.LNot, Exp.Var e1, _), _, _, _)],
@@ -406,7 +406,7 @@ let check_assignement_guard pdesc node =
             L.d_strln ("Found " ^ (Exp.to_string e') ^ " as prune var");
           [e']
       | _ -> [] in
-    let prune_vars = IList.flatten(IList.map (fun n -> prune_var n) succs) in
+    let prune_vars = List.concat(IList.map (fun n -> prune_var n) succs) in
     IList.for_all (fun e' -> Exp.equal e' e) prune_vars in
   let succs_loc = IList.map (fun n -> Procdesc.Node.get_loc n) succs in
   let succs_are_all_prune_nodes () =
@@ -441,8 +441,8 @@ let check_assignement_guard pdesc node =
      (* at this point all successors are at the same location, so we can take the first*)
      | loc_succ:: _ ->
          let set_instr_at_succs_loc =
-           IList.filter
+           List.filter
-             (fun i ->
+             ~f:(fun i ->
                  Location.equal (Sil.instr_get_loc i) loc_succ &&
                  is_set_instr i)
              instr in
@@ -616,17 +616,17 @@ let forward_tabulate tenv pdesc wl source =
     [reachable_hpreds]. *)
 let get_fld_typ_path_opt src_exps sink_exp_ reachable_hpreds_ =
   let strexp_matches target_exp = function
-    | (_, Sil.Eexp (e, _)) -> Exp.equal target_exp e
+    | Sil.Eexp (e, _) -> Exp.equal target_exp e
     | _ -> false in
   let extend_path hpred (sink_exp, path, reachable_hpreds) = match hpred with
     | Sil.Hpointsto (lhs, Sil.Estruct (flds, _), Exp.Sizeof (typ, _, _)) ->
-        (try
+        List.find ~f:(function _, se -> strexp_matches sink_exp se) flds |>
-           let fld, _ = IList.find (fun fld -> strexp_matches sink_exp fld) flds in
+        Option.value_map ~f:(function fld, _ ->
             let reachable_hpreds' = Sil.HpredSet.remove hpred reachable_hpreds in
-           (lhs, (Some fld, typ) :: path, reachable_hpreds')
+            (lhs, (Some fld, typ) :: path, reachable_hpreds'))
-         with Not_found -> (sink_exp, path, reachable_hpreds))
+          ~default:(sink_exp, path, reachable_hpreds)
     | Sil.Hpointsto (lhs, Sil.Earray (_, elems, _), Exp.Sizeof (typ, _, _)) ->
-        if List.exists ~f:(fun pair -> strexp_matches sink_exp pair) elems
+        if List.exists ~f:(function _, se -> strexp_matches sink_exp se) elems
         then
           let reachable_hpreds' = Sil.HpredSet.remove hpred reachable_hpreds in
           (* None means "no field name" ~=~ nameless array index *)
@@ -1405,7 +1405,7 @@ let interprocedural_algorithm exe_env : unit =
     let summary = Specs.get_summary_unsafe "main_algorithm" proc_name in
     Int.equal (Specs.get_timestamp summary) 0 in
   let procs_to_analyze =
-    IList.filter filter_initial (Cg.get_defined_nodes call_graph) in
+    List.filter ~f:filter_initial (Cg.get_defined_nodes call_graph) in
   let to_analyze proc_name =
     match Exe_env.get_proc_desc exe_env proc_name with
     | Some proc_desc ->

infer/src/backend/match.ml

@@ -41,7 +41,7 @@ let rec exp_match e1 sub vars e2 : (Sil.subst * Ident.t list) option =
     in if (Exp.equal e1 e2_inst) then Some(sub, vars) else None in
   match e1, e2 with
   | _, Exp.Var id2 when (Ident.is_primed id2 && mem_idlist id2 vars) ->
-      let vars_new = IList.filter (fun id -> not (Ident.equal id id2)) vars in
+      let vars_new = List.filter ~f:(fun id -> not (Ident.equal id id2)) vars in
       let sub_new = match (Sil.extend_sub sub id2 e1) with
         | None -> assert false (* happens when vars contains the same variable twice. *)
         | Some sub_new -> sub_new
@@ -545,7 +545,7 @@ and generate_todos_from_iel mode todos iel1 iel2 =
 let corres_extend_front e1 e2 corres =
   let filter (e1', e2') = (Exp.equal e1 e1') || (Exp.equal e2 e2') in
   let checker e1' e2' = (Exp.equal e1 e1') && (Exp.equal e2 e2')
-  in match (IList.filter filter corres) with
+  in match (List.filter ~f:filter corres) with
   | [] -> Some ((e1, e2) :: corres)
   | [(e1', e2')] when checker e1' e2' -> Some corres
   | _ -> None
@@ -557,7 +557,7 @@ let corres_extensible corres e1 e2 =
 let corres_related corres e1 e2 =
   let filter (e1', e2') = (Exp.equal e1 e1') || (Exp.equal e2 e2') in
   let checker e1' e2' = (Exp.equal e1 e1') && (Exp.equal e2 e2') in
-  match (IList.filter filter corres) with
+  match (List.filter ~f:filter corres) with
   | [] -> Exp.equal e1 e2
   | [(e1', e2')] when checker e1' e2' -> true
   | _ -> false
@@ -714,12 +714,12 @@ let generic_para_create tenv corres sigma1 elist1 =
     let not_same_consts = function
       | Exp.Const c1, Exp.Const c2 -> not (Const.equal c1 c2)
       | _ -> true in
-    let new_corres' = IList.filter not_same_consts corres in
+    let new_corres' = List.filter ~f:not_same_consts corres in
     let add_fresh_id pair = (pair, Ident.create_fresh Ident.kprimed) in
     IList.map add_fresh_id new_corres' in
   let (es_shared, ids_shared, ids_exists) =
     let not_in_elist1 ((e1, _), _) = not (List.exists ~f:(Exp.equal e1) elist1) in
-    let corres_ids_no_elist1 = IList.filter not_in_elist1 corres_ids in
+    let corres_ids_no_elist1 = List.filter ~f:not_in_elist1 corres_ids in
     let should_be_shared ((e1, e2), _) = Exp.equal e1 e2 in
     let shared, exists = IList.partition should_be_shared corres_ids_no_elist1 in
     let es_shared = IList.map (fun ((e1, _), _) -> e1) shared in
@@ -739,11 +739,10 @@ let hpara_create tenv corres sigma1 root1 next1 =
   let renaming, body, ids_exists, ids_shared, es_shared =
     generic_para_create tenv corres sigma1 [root1; next1] in
   let get_id1 e1 =
-    try
     let is_equal_to_e1 (e1', _) = Exp.equal e1 e1' in
-      let _, id = IList.find is_equal_to_e1 renaming in
+    match List.find ~f:is_equal_to_e1 renaming with
-      id
+    | Some (_, id) -> id
-    with Not_found -> assert false in
+    | None -> assert false in
   let id_root = get_id1 root1 in
   let id_next = get_id1 next1 in
   let hpara =
@@ -762,11 +761,10 @@ let hpara_dll_create tenv corres sigma1 root1 blink1 flink1 =
   let renaming, body, ids_exists, ids_shared, es_shared =
     generic_para_create tenv corres sigma1 [root1; blink1; flink1] in
   let get_id1 e1 =
-    try
     let is_equal_to_e1 (e1', _) = Exp.equal e1 e1' in
-      let _, id = IList.find is_equal_to_e1 renaming in
+    match List.find ~f:is_equal_to_e1 renaming with
-      id
+    | Some (_, id) -> id
-    with Not_found -> assert false in
+    | None -> assert false in
   let id_root = get_id1 root1 in
   let id_blink = get_id1 blink1 in
   let id_flink = get_id1 flink1 in

infer/src/backend/paths.ml

@@ -593,7 +593,7 @@ end = struct
   let filter f ps =
     let elements = ref [] in
     PropMap.iter (fun p _ -> elements := p :: !elements) ps;
-    elements := IList.filter (fun p -> not (f p)) !elements;
+    elements := List.filter ~f:(fun p -> not (f p)) !elements;
     let filtered_map = ref ps in
     IList.iter (fun p -> filtered_map := PropMap.remove p !filtered_map) !elements;
     !filtered_map

infer/src/backend/preanal.ml

@@ -212,7 +212,7 @@ let add_nullify_instrs pdesc tenv liveness_inv_map =
   let node_add_nullify_instructions node pvars =
     let loc = Procdesc.Node.get_last_loc node in
     let nullify_instrs =
-      IList.filter is_local pvars
+      List.filter ~f:is_local pvars
       |> IList.map (fun pvar -> Sil.Nullify (pvar, loc)) in
     if nullify_instrs <> []
     then Procdesc.Node.append_instrs node (IList.rev nullify_instrs) in

infer/src/backend/printer.ml

@@ -419,7 +419,7 @@ let write_proc_html source whole_seconds pdesc =
     begin
       let pname = Procdesc.get_proc_name pdesc in
       let nodes = IList.sort Procdesc.Node.compare (Procdesc.get_nodes pdesc) in
-      let linenum = (Procdesc.Node.get_loc (IList.hd nodes)).Location.line in
+      let linenum = (Procdesc.Node.get_loc (List.hd_exn nodes)).Location.line in
       let fd, fmt =
         Io_infer.Html.create
           (DB.Results_dir.Abs_source_dir source)

infer/src/backend/prop.ml

@@ -271,9 +271,9 @@ let create_pvar_env (sigma: sigma) : (Exp.t -> Exp.t) =
     | _ -> () in
   IList.iter filter sigma;
   let find e =
-    try
+    List.find ~f:(fun (e1, _) -> Exp.equal e1 e) !env |>
-      snd (IList.find (fun (e1, _) -> Exp.equal e1 e) !env)
+    Option.map ~f:snd |>
-    with Not_found -> e in
+    Option.value ~default:e in
   find
 
 (** Update the object substitution given the stack variables in the prop *)
@@ -412,10 +412,10 @@ let sigma_fav_in_pvars_add fav sigma =
   IList.iter (hpred_fav_in_pvars_add fav) sigma
 
 let sigma_fpv sigma =
-  IList.flatten (IList.map Sil.hpred_fpv sigma)
+  List.concat (IList.map Sil.hpred_fpv sigma)
 
 let pi_fpv pi =
-  IList.flatten (IList.map Sil.atom_fpv pi)
+  List.concat (IList.map Sil.atom_fpv pi)
 
 let prop_fpv prop =
   (Sil.sub_fpv prop.sub) @
@@ -1465,8 +1465,8 @@ module Normalize = struct
           lt_list_tightened in
       le_ineq_list @ lt_ineq_list in
     let nonineq_list' =
-      IList.filter
+      List.filter
-        (fun (a : Sil.atom) -> match a with
+        ~f:(fun (a : Sil.atom) -> match a with
             | Aneq (Const (Cint n), e)
             | Aneq (e, Const (Cint n)) ->
                 (not (List.exists
@@ -1512,7 +1512,7 @@ module Normalize = struct
     let pi' =
       IList.stable_sort
         Sil.compare_atom
-        ((IList.filter filter_useful_atom nonineq_list) @ ineq_list) in
+        ((List.filter ~f:filter_useful_atom nonineq_list) @ ineq_list) in
     let pi'' = pi_sorted_remove_redundant pi' in
     if equal_pi pi0 pi'' then pi0 else pi''
 
@@ -1550,7 +1550,7 @@ module Normalize = struct
   (** This function assumes that if (x,Exp.Var(y)) in sub, then compare x y = 1 *)
   let sub_normalize sub =
     let f (id, e) = (not (Ident.is_primed id)) && (not (Sil.ident_in_exp id e)) in
-    let sub' = Sil.sub_filter_pair f sub in
+    let sub' = Sil.sub_filter_pair ~f sub in
     if Sil.equal_subst sub sub' then sub else sub'
 
   (** Conjoin a pure atomic predicate by normal conjunction. *)
@@ -1924,9 +1924,9 @@ let prop_rename_array_indices tenv prop =
     let rec select_minimal_indices indices_seen = function
       | [] -> IList.rev indices_seen
       | index:: indices_rest ->
-          let indices_seen' = IList.filter (not_same_base_lt_offsets index) indices_seen in
+          let indices_seen' = List.filter ~f:(not_same_base_lt_offsets index) indices_seen in
           let indices_seen_new = index:: indices_seen' in
-          let indices_rest_new = IList.filter (not_same_base_lt_offsets index) indices_rest in
+          let indices_rest_new = List.filter ~f:(not_same_base_lt_offsets index) indices_rest in
           select_minimal_indices indices_seen_new indices_rest_new in
     let minimal_indices = select_minimal_indices [] indices in
     let subst = compute_reindexing_from_indices minimal_indices in
@@ -1936,7 +1936,7 @@ let prop_rename_array_indices tenv prop =
 let compute_renaming fav =
   let ids = Sil.fav_to_list fav in
   let ids_primed, ids_nonprimed = IList.partition Ident.is_primed ids in
-  let ids_footprint = IList.filter Ident.is_footprint ids_nonprimed in
+  let ids_footprint = List.filter ~f:Ident.is_footprint ids_nonprimed in
 
   let id_base_primed = Ident.create Ident.kprimed 0 in
   let id_base_footprint = Ident.create Ident.kfootprint 0 in
@@ -2190,7 +2190,7 @@ let remove_seed_captured_vars_block tenv captured_vars prop =
     | _ -> false in
   let sigma = prop.sigma in
   let sigma' =
-    IList.filter (fun hpred  -> not (hpred_seed_captured hpred)) sigma in
+    List.filter ~f:(fun hpred  -> not (hpred_seed_captured hpred)) sigma in
   Normalize.normalize tenv (set prop ~sigma:sigma')
 
 (** {2 Prop iterators} *)
@@ -2425,7 +2425,7 @@ let rec strexp_gc_fields (fav: Sil.fav) (se : Sil.strexp) =
   | Estruct (fsel, inst) ->
       let fselo = IList.map (fun (f, se) -> (f, strexp_gc_fields fav se)) fsel in
       let fsel' =
-        let fselo' = IList.filter (function | (_, Some _) -> true | _ -> false) fselo in
+        let fselo' = List.filter ~f:(function | (_, Some _) -> true | _ -> false) fselo in
         IList.map (function (f, seo) -> (f, unSome seo)) fselo' in
       if [%compare.equal: (Ident.fieldname * Sil.strexp) list] fsel fsel' then Some se
       else Some (Sil.Estruct (fsel', inst))
@@ -2567,8 +2567,8 @@ module CategorizePreconditions = struct
       let check_sigma sigma =
         IList.for_all hpred_filter sigma in
       check_pi pre.pi && check_sigma pre.sigma in
-    let pres_no_constraints = IList.filter (check_pre hpred_is_var) preconditions in
+    let pres_no_constraints = List.filter ~f:(check_pre hpred_is_var) preconditions in
-    let pres_only_allocation = IList.filter (check_pre hpred_only_allocation) preconditions in
+    let pres_only_allocation = List.filter ~f:(check_pre hpred_only_allocation) preconditions in
     match preconditions, pres_no_constraints, pres_only_allocation with
     | [], _, _ ->
         NoPres

infer/src/backend/propgraph.ml

@@ -79,7 +79,7 @@ let edge_from_source g n footprint_part is_hpred =
     match edge_get_source hpred with
     | Some e -> Exp.equal n e
     | None -> false in
-  match IList.filter starts_from edges with
+  match List.filter ~f:starts_from edges with
   | [] -> None
   | edge:: _ -> Some edge
 
@@ -106,8 +106,7 @@ let edge_equal e1 e2 = match e1, e2 with
 (** [contains_edge footprint_part g e] returns true if the graph [g] contains edge [e],
     searching the footprint part if [footprint_part] is true. *)
 let contains_edge (footprint_part: bool) (g: t) (e: edge) =
-  try ignore (IList.find (fun e' -> edge_equal e e') (get_edges footprint_part g)); true
+  List.exists ~f:(fun e' -> edge_equal e e') (get_edges footprint_part g)
-  with Not_found -> false
 
 (** [iter_edges footprint_part f g] iterates function [f] on the edges in [g] in the same order as returned by [get_edges];
     if [footprint_part] is true the edges are taken from the footprint part. *)
@@ -166,7 +165,7 @@ let compute_edge_diff (oldedge: edge) (newedge: edge) : Obj.t list = match olded
       compute_exp_diff e1 e2
   | Eatom (Sil.Apred (_, es1)), Eatom (Sil.Apred (_, es2))
   | Eatom (Sil.Anpred (_, es1)), Eatom (Sil.Anpred (_, es2)) ->
-      IList.flatten (try IList.map2 compute_exp_diff es1 es2 with IList.Fail -> [])
+      List.concat (try IList.map2 compute_exp_diff es1 es2 with IList.Fail -> [])
   | Esub_entry (_, e1), Esub_entry (_, e2) ->
       compute_exp_diff e1 e2
   | _ -> [Obj.repr newedge]

infer/src/backend/propset.ml

@@ -72,7 +72,7 @@ let to_proplist pset =
 (** Apply function to all the elements of [propset], removing those where it returns [None]. *)
 let map_option tenv f pset =
   let plisto = IList.map f (to_proplist pset) in
-  let plisto = IList.filter (function | Some _ -> true | None -> false) plisto in
+  let plisto = List.filter ~f:(function | Some _ -> true | None -> false) plisto in
   let plist = IList.map (function Some p -> p | None -> assert false) plisto in
   from_proplist tenv plist
 

infer/src/backend/prover.ml

@@ -20,10 +20,10 @@ let decrease_indent_when_exception thunk =
   with exn when SymOp.exn_not_failure exn -> (L.d_decrease_indent 1; raise exn)
 
 let compute_max_from_nonempty_int_list l =
-  IList.hd (IList.rev (IList.sort IntLit.compare_value l))
+  uw (List.max_elt ~cmp:IntLit.compare_value l)
 
 let compute_min_from_nonempty_int_list l =
-  IList.hd (IList.sort IntLit.compare_value l)
+  uw (List.min_elt ~cmp:IntLit.compare_value l)
 
 let rec list_rev_acc acc = function
   | [] -> acc
@@ -129,7 +129,7 @@ end = struct
 
   let remove_redundancy constraints =
     let constraints' = sort_then_remove_redundancy constraints in
-    IList.filter (fun entry -> List.exists ~f:(equal entry) constraints') constraints
+    List.filter ~f:(fun entry -> List.exists ~f:(equal entry) constraints') constraints
 
   let rec combine acc_todos acc_seen constraints_new constraints_old =
     match constraints_new, constraints_old with
@@ -477,7 +477,7 @@ end = struct
     | Exp.Const (Const.Cint n1) -> Some n1
     | _ ->
         let e_upper_list =
-          IList.filter (function
+          List.filter ~f:(function
               | e', Exp.Const (Const.Cint _) -> Exp.equal e1 e'
               | _, _ -> false) leqs in
         let upper_list =
@@ -494,7 +494,7 @@ end = struct
     | Exp.Sizeof _ -> Some IntLit.zero
     | _ ->
         let e_lower_list =
-          IList.filter (function
+          List.filter ~f:(function
               | Exp.Const (Const.Cint _), e' -> Exp.equal e1 e'
               | _, _ -> false) lts in
         let lower_list =
@@ -2143,7 +2143,7 @@ let check_implication_base pname tenv check_frame_empty calc_missing prop1 prop2
     let filter (id, e) =
       Ident.is_normal id && Sil.fav_for_all (Sil.exp_fav e) Ident.is_normal in
     let sub1_base =
-      Sil.sub_filter_pair filter prop1.Prop.sub in
+      Sil.sub_filter_pair ~f:filter prop1.Prop.sub in
     let pi1, pi2 = Prop.get_pure prop1, Prop.get_pure prop2 in
     let sigma1, sigma2 = prop1.Prop.sigma, prop2.Prop.sigma in
     let subs = pre_check_pure_implication tenv calc_missing (prop1.Prop.sub, sub1_base) pi1 pi2 in

infer/src/backend/rearrange.ml

@@ -105,8 +105,10 @@ 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.equal_fieldname f f') (fields @ statics) with
+            match List.find
-            | _, t', _ ->
+                    ~f:(fun (f', _, _) -> Ident.equal_fieldname f f')
+                    (fields @ statics) with
+            | Some (_, t', _) ->
                 let atoms', se', res_t' =
                   create_struct_values
                     pname tenv orig_prop footprint_part kind max_stamp t' off' inst in
@@ -117,7 +119,7 @@ let rec create_struct_values pname tenv orig_prop footprint_part kind max_stamp
                   IList.sort StructTyp.compare_field (IList.map replace_typ_of_f fields) in
                 ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
                 (atoms', se, t)
-            | exception Not_found ->
+            | None ->
                 fail t off __POS__
           )
         | None ->
@@ -206,10 +208,10 @@ 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) -> (
-          match IList.find (fun (f', _, _) -> Ident.equal_fieldname f f') (fields @ statics) with
+          match List.find ~f:(fun (f', _, _) -> Ident.equal_fieldname f f') (fields @ statics) with
-          | _, typ', _ -> (
+          | Some (_, typ', _) -> (
-              match IList.find (fun (f', _) -> Ident.equal_fieldname f f') fsel with
+              match List.find ~f:(fun (f', _) -> Ident.equal_fieldname f f') fsel with
-              | _, se' ->
+              | Some (_, se') ->
                   let atoms_se_typ_list' =
                     _strexp_extend_values
                       pname tenv orig_prop footprint_part kind max_stamp se' typ' off' inst in
@@ -217,7 +219,9 @@ let rec _strexp_extend_values
                     let replace_fse ((f1, _) as ft1) =
                       if Ident.equal_fieldname f1 f then (f1, res_se') else ft1 in
                     let res_fsel' =
-                      IList.sort [%compare: Ident.fieldname * Sil.strexp] (IList.map replace_fse fsel) in
+                      IList.sort
+                        [%compare: Ident.fieldname * Sil.strexp]
+                        (IList.map replace_fse fsel) in
                     let replace_fta ((f1, _, a1) as fta1) =
                       if Ident.equal_fieldname f f1 then (f1, res_typ', a1) else fta1 in
                     let fields' =
@@ -225,11 +229,12 @@ let rec _strexp_extend_values
                     ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
                     (res_atoms', Sil.Estruct (res_fsel', inst'), typ) :: acc in
                   IList.fold_left replace [] atoms_se_typ_list'
-              | exception Not_found ->
+              | None ->
                   let atoms', se', res_typ' =
                     create_struct_values
                       pname tenv orig_prop footprint_part kind max_stamp typ' off' inst in
-                  let res_fsel' = IList.sort [%compare: Ident.fieldname * Sil.strexp] ((f, se'):: fsel) in
+                  let res_fsel' =
+                    IList.sort [%compare: Ident.fieldname * Sil.strexp] ((f, se'):: fsel) in
                   let replace_fta (f', t', a') =
                     if Ident.equal_fieldname f' f then (f, res_typ', a') else (f', t', a') in
                   let fields' =
@@ -237,7 +242,7 @@ let rec _strexp_extend_values
                   ignore (Tenv.mk_struct tenv ~default:struct_typ ~fields:fields' name) ;
                   [(atoms', Sil.Estruct (res_fsel', inst'), typ)]
             )
-          | exception Not_found ->
+          | None ->
               raise (Exceptions.Missing_fld (f, __POS__))
         )
       | None ->
@@ -260,8 +265,8 @@ let rec _strexp_extend_values
         pname tenv orig_prop footprint_part kind max_stamp se_new typ_new off inst
   | (Off_index e) :: off', Sil.Earray (len, esel, inst_arr), Tarray (typ', len_for_typ') -> (
       bounds_check tenv pname orig_prop len e (State.get_loc ());
-      match IList.find (fun (e', _) -> Exp.equal e e') esel with
+      match List.find ~f:(fun (e', _) -> Exp.equal e e') esel with
-      | _, se' ->
+      | Some (_, se') ->
           let atoms_se_typ_list' =
             _strexp_extend_values
               pname tenv orig_prop footprint_part kind max_stamp se' typ' off' inst in
@@ -276,7 +281,7 @@ let rec _strexp_extend_values
             else
               raise (Exceptions.Bad_footprint __POS__) in
           IList.fold_left replace [] atoms_se_typ_list'
-      | exception Not_found ->
+      | None ->
           array_case_analysis_index pname tenv orig_prop
             footprint_part kind max_stamp
             len esel
@@ -330,7 +335,7 @@ and array_case_analysis_index pname tenv orig_prop
         [(atoms, array_new, typ_new)]
       end in
     let rec handle_case acc isel_seen_rev = function
-      | [] -> IList.flatten (IList.rev (res_new:: acc))
+      | [] -> List.concat (IList.rev (res_new:: acc))
       | (i, se) as ise :: isel_unseen ->
           let atoms_se_typ_list =
             _strexp_extend_values
@@ -397,7 +402,7 @@ let strexp_extend_values
   let atoms_se_typ_list_filtered =
     let check_neg_atom atom = Prover.check_atom tenv Prop.prop_emp (Prover.atom_negate tenv atom) in
     let check_not_inconsistent (atoms, _, _) = not (List.exists ~f:check_neg_atom atoms) in
-    IList.filter check_not_inconsistent atoms_se_typ_list in
+    List.filter ~f:check_not_inconsistent atoms_se_typ_list in
   if Config.trace_rearrange then L.d_strln "exiting strexp_extend_values";
   let len, st = match te with
     | Exp.Sizeof(_, len, st) -> (len, st)
@@ -468,10 +473,10 @@ let prop_iter_check_fields_ptsto_shallow tenv iter lexp =
     | (Sil.Off_fld (fld, _)):: off' ->
         (match se with
          | Sil.Estruct (fsel, _) ->
-             (try
+             (match List.find ~f:(fun (fld', _) -> Ident.equal_fieldname fld fld') fsel with
-                let _, se' = IList.find (fun (fld', _) -> Ident.equal_fieldname fld fld') fsel in
+              | Some (_, se') ->
                   check_offset se' off'
-              with Not_found -> Some fld)
+              | None -> Some fld)
          | _ -> Some fld)
     | (Sil.Off_index _):: _ -> None in
   check_offset se offset
@@ -669,7 +674,7 @@ let add_guarded_by_constraints tenv prop lexp pdesc =
             None
       else
         None in
-    IList.find_map_opt annot_extract_guarded_by_str item_annot in
+    List.find_map ~f:annot_extract_guarded_by_str item_annot in
   let extract_suppress_warnings_str item_annot =
     let annot_suppress_warnings_str ((annot: Annot.t), _) =
       if Annotations.annot_ends_with annot Annotations.suppress_lint
@@ -681,7 +686,7 @@ let add_guarded_by_constraints tenv prop lexp pdesc =
             None
       else
         None in
-    IList.find_map_opt annot_suppress_warnings_str item_annot in
+    List.find_map ~f:annot_suppress_warnings_str item_annot in
   (* if [fld] is annotated with @GuardedBy("mLock"), return mLock *)
   let get_guarded_by_fld_str fld typ =
     match StructTyp.get_field_type_and_annotation ~lookup fld typ with
@@ -709,7 +714,7 @@ let add_guarded_by_constraints tenv prop lexp pdesc =
         match StructTyp.get_field_type_and_annotation ~lookup fld typ with
         | Some (fld_typ, _) when f fld fld_typ -> Some (strexp, fld_typ)
         | _ -> None in
-      IList.find_map_opt match_one flds in
+      List.find_map ~f:match_one flds in
 
     (* sometimes, programmers will write @GuardedBy("T.f") with the meaning "guarded by the field f
        of the object of type T in the current state." note that this is ambiguous when there are
@@ -725,11 +730,12 @@ let add_guarded_by_constraints tenv prop lexp pdesc =
           begin
             match get_fld_strexp_and_typ typ typ_matches_guarded_by flds with
             | Some (Sil.Eexp (matching_exp, _), _) ->
-                IList.find_map_opt
+                List.find_map
-                  (function
+                  ~f:(function
                       | Sil.Hpointsto (lhs_exp, Estruct (matching_flds, _), Sizeof (fld_typ, _, _))
                         when Exp.equal lhs_exp matching_exp ->
-                        get_fld_strexp_and_typ fld_typ (is_guarded_by_fld field_part) matching_flds
+                          get_fld_strexp_and_typ
+                            fld_typ (is_guarded_by_fld field_part) matching_flds
                       | _ ->
                           None)
                   sigma
@@ -739,8 +745,8 @@ let add_guarded_by_constraints tenv prop lexp pdesc =
       | _ ->
           None in
 
-    IList.find_map_opt
+    List.find_map
-      (function
+      ~f:(function
           | Sil.Hpointsto ((Const (Cclass clazz) as lhs_exp), _, Exp.Sizeof (typ, _, _))
           | Sil.Hpointsto (_, Sil.Eexp (Const (Cclass clazz) as lhs_exp, _), Exp.Sizeof (typ, _, _))
             when guarded_by_str_is_class guarded_by_str0 (Ident.name_to_string clazz) ->
@@ -981,7 +987,7 @@ let iter_rearrange_ptsto pname tenv orig_prop iter lexp inst =
             let filter it =
               let p = Prop.prop_iter_to_prop tenv it in
               not (Prover.check_inconsistency tenv p) in
-            IList.filter filter (IList.map handle_case atoms_se_te_list)
+            List.filter ~f:filter (IList.map handle_case atoms_se_te_list)
         | _ -> [iter]
       end in
   begin
@@ -1109,9 +1115,9 @@ 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.equal_fieldname f f') fields with
+            match List.find ~f:(fun (f', _, _) -> Ident.equal_fieldname f f') fields with
-            | _, typ', _ -> strip_offset off' typ'
+            | Some (_, typ', _) -> strip_offset off' typ'
-            | exception Not_found -> None
+            | None -> None
           )
         | None ->
             None
@@ -1209,7 +1215,7 @@ let rec iter_rearrange
       else
         iter_rearrange pname tenv (Prop.lexp_normalize_prop tenv prop' lexp) typ prop' iter' inst in
     let rec f_many_iters iters_lst = function
-      | [] -> IList.flatten (IList.rev iters_lst)
+      | [] -> List.concat (IList.rev iters_lst)
       | iter':: iters' ->
           let iters_res' = f_one_iter iter' in
           f_many_iters (iters_res':: iters_lst) iters' in

infer/src/backend/state.ml

@@ -215,7 +215,7 @@ let mk_find_duplicate_nodes proc_desc : (Procdesc.Node.t -> Procdesc.NodeSet.t)
       let duplicates =
         let equal_normalized_instrs (_, normalized_instrs') =
           List.equal ~equal:Sil.equal_instr node_normalized_instrs normalized_instrs' in
-        IList.filter equal_normalized_instrs elements in
+        List.filter ~f:equal_normalized_instrs elements in
       IList.fold_left
         (fun nset (node', _) -> Procdesc.NodeSet.add node' nset)
         Procdesc.NodeSet.empty duplicates

infer/src/backend/symExec.ml

@@ -46,7 +46,7 @@ let unroll_type tenv (typ: Typ.t) (off: Sil.offset) =
 
 (** Given a node, returns a list of pvar of blocks that have been nullified in the block. *)
 let get_blocks_nullified node =
-  let null_blocks = IList.flatten(IList.map (fun i -> match i with
+  let null_blocks = List.concat (IList.map (fun i -> match i with
       | Sil.Nullify(pvar, _) when Sil.is_block_pvar pvar -> [pvar]
       | _ -> []) (Procdesc.Node.get_instrs node)) in
   null_blocks
@@ -142,8 +142,8 @@ 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.equal_fieldname fld (fst fse)) fsel with
+          match List.find ~f:(fun fse -> Ident.equal_fieldname fld (fst fse)) fsel with
-          | _, se' ->
+          | Some (_, se') ->
               let res_e', res_se', res_t', res_pred_insts_op' =
                 apply_offlist
                   pdesc tenv p fp_root nullify_struct
@@ -156,7 +156,7 @@ let rec apply_offlist
               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')
-          | exception Not_found ->
+          | None ->
               (* This case should not happen. The rearrangement should
                  have materialized all the accessed cells. *)
               pp_error();
@@ -172,8 +172,8 @@ let rec apply_offlist
 
   | (Sil.Off_index idx) :: offlist', Sil.Earray (len, esel, inst1), Typ.Tarray (t', len') -> (
       let nidx = Prop.exp_normalize_prop tenv p idx in
-      try
+      match List.find ~f:(fun ese -> Prover.check_equal tenv p nidx (fst ese)) esel with
-        let idx_ese', se' = IList.find (fun ese -> Prover.check_equal tenv p nidx (fst ese)) esel in
+      | Some (idx_ese', se') ->
           let res_e', res_se', res_t', res_pred_insts_op' =
             apply_offlist
               pdesc tenv p fp_root nullify_struct
@@ -185,13 +185,12 @@ let rec apply_offlist
           let res_se = Sil.Earray (len, IList.map replace_ese esel, inst1) in
           let res_t = Typ.Tarray (res_t', len') in
           (res_e', res_se, res_t, res_pred_insts_op')
-      with Not_found ->
+      | None ->
           (* return a nondeterministic value if the index is not found after rearrangement *)
           L.d_str "apply_offlist: index "; Sil.d_exp idx;
           L.d_strln " not materialized -- returning nondeterministic value";
           let res_e' = Exp.Var (Ident.create_fresh Ident.kprimed) in
-        (res_e', strexp, typ, None)
+          (res_e', strexp, typ, None))
-    )
   | (Sil.Off_index _) :: _, _, _ ->
       (* This case should not happen. The rearrangement should
          have materialized all the accessed cells. *)
@@ -423,10 +422,9 @@ let check_arith_norm_exp tenv pname exp prop =
 (** Check if [cond] is testing for NULL a pointer already dereferenced *)
 let check_already_dereferenced tenv pname cond prop =
   let find_hpred lhs =
-    try Some (IList.find (function
+    List.find ~f:(function
         | Sil.Hpointsto (e, _, _) -> Exp.equal e lhs
-        | _ -> false) prop.Prop.sigma)
+        | _ -> false) prop.Prop.sigma in
-    with Not_found -> None in
   let rec is_check_zero = function
     | Exp.Var id ->
         Some id
@@ -568,7 +566,7 @@ let resolve_virtual_pname tenv prop actuals callee_pname call_flags : Procname.t
           let target_receiver_typ = get_receiver_typ target_pname actual_receiver_typ in
           Prover.Subtyping_check.check_subtype tenv target_receiver_typ actual_receiver_typ in
         let resolved_pname = do_resolve callee_pname receiver_exp actual_receiver_typ in
-        let feasible_targets = IList.filter may_dispatch_to targets in
+        let feasible_targets = List.filter ~f:may_dispatch_to targets in
         (* make sure [resolved_pname] is not a duplicate *)
         if List.mem ~equal:Procname.equal feasible_targets resolved_pname
         then feasible_targets
@@ -748,7 +746,7 @@ let handle_objc_instance_method_call_or_skip tenv actual_pars path callee_pname
         let propset = prune_ne tenv ~positive:false receiver Exp.zero pre_with_attr_or_null in
         if Propset.is_empty propset then []
         else
-          let prop = IList.hd (Propset.to_proplist propset) in
+          let prop = List.hd_exn (Propset.to_proplist propset) in
           let path = Paths.Path.add_description path path_description in
           [(prop, path)] in
       res_null @ (res ())
@@ -1161,7 +1159,7 @@ let rec sym_exec tenv current_pdesc _instr (prop_: Prop.normal Prop.t) path
                 else
                   proc_call (Option.value_exn resolved_summary_opt)
                     (call_args prop resolved_pname n_actual_params ret_id loc) in
-              IList.flatten (IList.map do_call sentinel_result)
+              List.concat (IList.map do_call sentinel_result)
         )
     )
   | Sil.Call (ret_id, fun_exp, actual_params, loc, call_flags) -> (* Call via function pointer *)
@@ -1244,7 +1242,7 @@ and instrs ?(mask_errors=false) tenv pdesc instrs ppl =
         ("Generated Instruction Failed with: " ^
          (Localise.to_string err_name)^loc ); L.d_ln();
       [(p, path)] in
-  let f plist instr = IList.flatten (IList.map (exe_instr instr) plist) in
+  let f plist instr = List.concat (IList.map (exe_instr instr) plist) in
   IList.fold_left f ppl instrs
 
 and add_constraints_on_actuals_by_ref tenv prop actuals_by_ref callee_pname callee_loc =
@@ -1301,8 +1299,8 @@ and add_constraints_on_actuals_by_ref tenv prop actuals_by_ref callee_pname call
           (* bind actual passed by ref to the abduced value pointed to by the synthetic pvar *)
           let prop' =
             let filtered_sigma =
-              IList.filter
+              List.filter
-                (function
+                ~f:(function
                     | Sil.Hpointsto (lhs, _, _) when Exp.equal lhs actual ->
                         false
                     | _ -> true)
@@ -1341,7 +1339,7 @@ and add_constraints_on_actuals_by_ref tenv prop actuals_by_ref callee_pname call
           not is_const
       | None ->
           true in
-    IList.filter is_not_const actuals_by_ref in
+    List.filter ~f:is_not_const actuals_by_ref in
   IList.fold_left do_actual_by_ref prop non_const_actuals_by_ref
 
 and check_untainted tenv exp taint_kind caller_pname callee_pname prop =
@@ -1391,11 +1389,10 @@ and unknown_or_scan_call ~is_scan ret_type_option ret_annots
       | param_nums ->
           let check_taint_if_nums_match (prop_acc, param_num) (actual_exp, _actual_typ) =
             let prop_acc' =
-              try
+              match List.find ~f:(fun (num, _) -> Int.equal num param_num) param_nums with
-                let _, taint_kind =
+              | Some (_, taint_kind) ->
-                  IList.find (fun (num, _) -> Int.equal num param_num) param_nums in
                   check_untainted tenv actual_exp taint_kind caller_pname callee_pname prop_acc
-              with Not_found -> prop_acc in
+              | None -> prop_acc in
             prop_acc', param_num + 1 in
           IList.fold_left
             check_taint_if_nums_match

infer/src/backend/tabulation.ml

@@ -156,7 +156,7 @@ let process_splitting
   let sub = Sil.sub_join sub1 sub2 in
   let sub1_inverse =
     let sub1_list = Sil.sub_to_list sub1 in
-    let sub1_list' = IList.filter (function (_, Exp.Var _) -> true | _ -> false) sub1_list in
+    let sub1_list' = List.filter ~f:(function (_, Exp.Var _) -> true | _ -> false) sub1_list in
     let sub1_inverse_list =
       IList.map
         (function (id, Exp.Var id') -> (id', Exp.Var id) | _ -> assert false)
@@ -243,7 +243,7 @@ let process_splitting
         | _ ->
             L.d_warning "Missing fields in complex pred: "; Sil.d_hpred hpred; L.d_ln ();
             false in
-    IList.filter filter sigma in
+    List.filter ~f:filter sigma in
   let norm_frame = Prop.sigma_sub sub' frame in
   { sub =           sub';
     frame =         norm_frame;
@@ -342,14 +342,14 @@ let check_dereferences tenv callee_pname actual_pre sub spec_pre formal_params =
            a less interesting PRECONDITION_NOT_MET
          * whenever possible *)
         (* TOOD (t4893533): use this trick outside of angelic mode and in other parts of the code *)
-        Some
+        (match
-          (try
+           List.find
-             IList.find
+             ~f:(fun err -> match err with
-               (fun err -> match err with
                  | (Deref_null _, _) -> true
                  | _ -> false )
-               deref_err_list
+             deref_err_list with
-           with Not_found -> deref_err)
+        | Some x -> Some x
+        | None -> Some deref_err)
       else Some deref_err
 
 let post_process_sigma tenv (sigma: Sil.hpred list) loc : Sil.hpred list =
@@ -720,7 +720,8 @@ let combine tenv
       let post_sigma = sigma_star_fld tenv post_p.Prop.sigma split.frame_fld in
       let post_sigma' = sigma_star_typ post_sigma split.frame_typ in
       Prop.set post_p ~sigma:post_sigma' in
-    let post_p1 = Prop.prop_sigma_star (prop_copy_footprint_pure tenv actual_pre post_p') split.frame in
+    let post_p1 =
+      Prop.prop_sigma_star (prop_copy_footprint_pure tenv actual_pre post_p') split.frame in
 
     let handle_null_case_analysis sigma =
       let id_assigned_to_null id =
@@ -838,7 +839,10 @@ let check_taint_on_variadic_function tenv callee_pname caller_pname actual_param
   | [(tp, _)] when tp < 0 ->
       (* All actual params from abs(tp) should not be tainted. If we find one we give the warning *)
       let tp_abs = abs tp in
-      L.d_strln ("Checking tainted actual parameters from parameter number "^ (string_of_int tp_abs) ^ " onwards.");
+      L.d_strln
+        ("Checking tainted actual parameters from parameter number " ^
+         (string_of_int tp_abs) ^
+         " onwards.");
       let actual_params' = n_tail actual_params tp_abs in
       L.d_str "Paramters to be checked:  [ ";
       IList.iter(fun (e,_) ->
@@ -903,7 +907,7 @@ let mk_posts tenv ret_id prop callee_pname callee_attrs posts =
                       Prover.check_equal tenv (Prop.normalize tenv prop) e Exp.zero
                   | _ -> false)
               prop.Prop.sigma in
-          IList.filter (fun (prop, _) -> not (returns_null prop)) posts
+          List.filter ~f:(fun (prop, _) -> not (returns_null prop)) posts
         else posts in
       let mk_retval_tainted posts =
         match Taint.returns_tainted callee_pname (Some callee_attrs) with
@@ -982,7 +986,7 @@ let do_taint_check tenv caller_pname callee_pname calling_prop missing_pi sub ac
               untaint_atoms)
          taint_untaint_exp_map) in
   check_taint_on_variadic_function tenv callee_pname caller_pname actual_params calling_prop;
-  IList.filter not_untaint_atom missing_pi_sub
+  List.filter ~f:not_untaint_atom missing_pi_sub
 
 let class_cast_exn tenv pname_opt texp1 texp2 exp ml_loc =
   let desc =
@@ -1081,7 +1085,7 @@ let exe_spec
               | _ -> false in
             (* missing fields minus hidden fields *)
             let missing_fld_nohidden =
-              IList.filter (fun hp -> not (hpred_missing_hidden hp)) missing_fld in
+              List.filter ~f:(fun hp -> not (hpred_missing_hidden hp)) missing_fld in
             if not !Config.footprint && split.missing_sigma <> [] then
               begin
                 L.d_strln "Implication error: missing_sigma not empty in re-execution";
@@ -1099,15 +1103,16 @@ let remove_constant_string_class tenv prop =
   let filter = function
     | Sil.Hpointsto (Exp.Const (Const.Cstr _ | Const.Cclass _), _, _) -> false
     | _ -> true in
-  let sigma = IList.filter filter prop.Prop.sigma in
+  let sigma = List.filter ~f:filter prop.Prop.sigma in
-  let sigmafp = IList.filter filter prop.Prop.sigma_fp in
+  let sigmafp = List.filter ~f:filter prop.Prop.sigma_fp in
   let prop' = Prop.set prop ~sigma ~sigma_fp:sigmafp in
   Prop.normalize tenv prop'
 
 (** existentially quantify the path identifier generated
     by the prover to keep track of expansions of lhs paths
     and remove pointsto's whose lhs is a constant string *)
-let quantify_path_idents_remove_constant_strings tenv (prop: Prop.normal Prop.t) : Prop.normal Prop.t =
+let quantify_path_idents_remove_constant_strings tenv (prop: Prop.normal Prop.t)
+  : Prop.normal Prop.t =
   let fav = Prop.prop_fav prop in
   Sil.fav_filter_ident fav Ident.is_path;
   remove_constant_string_class tenv (Prop.exist_quantify tenv fav prop)
@@ -1120,7 +1125,7 @@ let prop_pure_to_footprint tenv (p: 'a Prop.t) : Prop.normal Prop.t =
     let a_fav = Sil.atom_fav a in
     Sil.fav_for_all a_fav Ident.is_footprint in
   let pure = Prop.get_pure p in
-  let new_footprint_atoms = IList.filter is_footprint_atom_not_attribute pure in
+  let new_footprint_atoms = List.filter ~f:is_footprint_atom_not_attribute pure in
   if List.is_empty new_footprint_atoms
   then p
   else (* add pure fact to footprint *)
@@ -1141,7 +1146,8 @@ let exe_call_postprocess tenv ret_id trace_call callee_pname callee_attrs loc re
     IList.partition (fun vr -> vr.vr_pi <> []) valid_res in
   let _, valid_res_cons_pre_missing =
     IList.partition (fun vr -> vr.incons_pre_missing) valid_res in
-  let deref_errors = IList.filter (function Dereference_error _ -> true | _ -> false) invalid_res in
+  let deref_errors =
+    List.filter ~f:(function Dereference_error _ -> true | _ -> false) invalid_res in
   let print_pi pi =
     L.d_str "pi: "; Prop.d_pi pi; L.d_ln () in
   let call_desc kind_opt = Localise.desc_precondition_not_met kind_opt callee_pname loc in
@@ -1151,7 +1157,8 @@ let exe_call_postprocess tenv ret_id trace_call callee_pname callee_attrs loc re
         if List.is_empty valid_res_cons_pre_missing then
           (* no valid results where actual pre and missing are consistent *)
           begin
-            if deref_errors <> [] then (* dereference error detected *)
+            match deref_errors with
+            | error :: _ -> (* dereference error detected *)
                 let extend_path path_opt path_pos_opt = match path_opt with
                   | None -> ()
                   | Some path_post ->
@@ -1160,7 +1167,7 @@ let exe_call_postprocess tenv ret_id trace_call callee_pname callee_attrs loc re
                         Paths.Path.add_call
                           (include_subtrace callee_pname) old_path callee_pname path_post in
                       State.set_path new_path path_pos_opt in
-              match IList.hd deref_errors with
+                (match error with
                  | Dereference_error (Deref_minusone, desc, path_opt) ->
                      trace_call Specs.CallStats.CR_not_met;
                      extend_path path_opt None;
@@ -1194,8 +1201,8 @@ let exe_call_postprocess tenv ret_id trace_call callee_pname callee_attrs loc re
                  | Missing_sigma_not_empty
                  | Missing_fld_not_empty ->
                      trace_call Specs.CallStats.CR_not_met;
-                  assert false
+                     assert false)
-            else (* no dereference error detected *)
+            | [] -> (* no dereference error detected *)
                 let desc =
                   if List.exists ~f:(function Cannot_combine -> true | _ -> false) invalid_res then
                     call_desc (Some Localise.Pnm_dangling)
@@ -1224,10 +1231,10 @@ let exe_call_postprocess tenv ret_id trace_call callee_pname callee_attrs loc re
             vr.vr_cons_res in
           IList.map
             (fun (p, path) -> (prop_pure_to_footprint tenv p, path))
-            (IList.flatten (IList.map process_valid_res valid_res))
+            (List.concat (IList.map process_valid_res valid_res))
       end
     else if valid_res_no_miss_pi <> [] then
-      IList.flatten (IList.map (fun vr -> vr.vr_cons_res) valid_res_no_miss_pi)
+      List.concat (IList.map (fun vr -> vr.vr_cons_res) valid_res_no_miss_pi)
     else if List.is_empty valid_res_miss_pi then
       raise (Exceptions.Precondition_not_met (call_desc None, __POS__))
     else
@@ -1243,7 +1250,7 @@ let exe_call_postprocess tenv ret_id trace_call callee_pname callee_attrs loc re
         | Some cover ->
             L.d_strln "Found minimum cover";
             IList.iter print_pi (IList.map fst cover);
-            IList.flatten (IList.map snd cover)
+            List.concat (IList.map snd cover)
       end in
   trace_call Specs.CallStats.CR_success;
   let res =

infer/src/backend/taint.ml

@@ -306,10 +306,10 @@ let attrs_opt_get_annots = function
 let returns_tainted callee_pname callee_attrs_opt =
   let procname_matches taint_info =
     Procname.equal taint_info.PredSymb.taint_source callee_pname in
-  try
+  match List.find ~f:procname_matches sources with
-    let taint_info = IList.find procname_matches sources in
+  | Some taint_info ->
       Some taint_info.PredSymb.taint_kind
-  with Not_found ->
+  | None ->
       let ret_annot, _ = attrs_opt_get_annots callee_attrs_opt in
       if Annotations.ia_is_integrity_source ret_annot
       then Some PredSymb.Tk_integrity_annotation
@@ -318,12 +318,9 @@ let returns_tainted callee_pname callee_attrs_opt =
       else None
 
 let find_callee taint_infos callee_pname =
-  try
+  List.find
-    Some
+    ~f:(fun (taint_info, _) -> Procname.equal taint_info.PredSymb.taint_source callee_pname)
-      (IList.find
+    taint_infos
-         (fun (taint_info, _) -> Procname.equal taint_info.PredSymb.taint_source callee_pname)
-         taint_infos)
-  with Not_found -> None
 
 (** returns list of zero-indexed argument numbers of [callee_pname] that may be tainted *)
 let accepts_sensitive_params callee_pname callee_attrs_opt =
@@ -361,8 +358,7 @@ let has_taint_annotation fieldname (struct_typ: StructTyp.t) =
 (* add tainting attributes to a list of paramenters *)
 let get_params_to_taint tainted_param_nums formal_params =
   let get_taint_kind index =
-    try Some (IList.find (fun (taint_index, _) -> Int.equal index taint_index) tainted_param_nums)
+    List.find ~f:(fun (taint_index, _) -> Int.equal index taint_index) tainted_param_nums in
-    with Not_found -> None in
   let collect_params_to_taint params_to_taint_acc (index, param) =
     match get_taint_kind index with
     | Some (_, taint_kind) -> (param, taint_kind) :: params_to_taint_acc

infer/src/base/CommandLineOption.ml

@@ -181,7 +181,7 @@ let pad_and_xform doc_width left_width desc =
             wrap_line "" doc_width s
           else [s] in
         IList.map wrap_line lines in
-      let doc = indent_doc (String.concat ~sep:"\n" (IList.flatten wrapped_lines)) in
+      let doc = indent_doc (String.concat ~sep:"\n" (List.concat wrapped_lines)) in
       xdesc {desc with doc}
 
 let align desc_list =
@@ -325,7 +325,7 @@ type 'a t =
 
 let string_json_decoder ~long json = [dashdash long; YBU.to_string json]
 
-let list_json_decoder json_decoder json = IList.flatten (YBU.convert_each json_decoder json)
+let list_json_decoder json_decoder json = List.concat (YBU.convert_each json_decoder json)
 
 let mk_set var value ?(deprecated=[]) ~long ?short ?parse_mode ?(meta="") doc =
   let setter () = var := value in
@@ -544,6 +544,7 @@ let mk_rest ?(parse_mode=Infer []) doc =
 
 let set_curr_speclist_for_parse_action ~incomplete ~usage parse_action =
   let full_speclist = ref [] in
+
   let curr_usage status =
     prerr_endline (String.concat_array ~sep:" " !args_to_parse) ;
     Arg.usage !curr_speclist usage ;
@@ -626,8 +627,8 @@ let set_curr_speclist_for_parse_action ~incomplete ~usage parse_action =
       opt = "" ||
       IList.for_all (fun (opt', _, doc') ->
           (doc <> "" && doc' = "") || (not (String.equal opt opt'))) speclist in
-    let unique_exe_speclist = IList.filter (is_not_dup_with_doc !curr_speclist) exe_speclist in
+    let unique_exe_speclist = List.filter ~f:(is_not_dup_with_doc !curr_speclist) exe_speclist in
-    curr_speclist := IList.filter (is_not_dup_with_doc unique_exe_speclist) !curr_speclist @
+    curr_speclist := List.filter ~f:(is_not_dup_with_doc unique_exe_speclist) !curr_speclist @
                      (match header with
                       | Some s -> (to_arg_spec_triple (mk_header_spec s)):: unique_exe_speclist
                       | None -> unique_exe_speclist)
@@ -682,8 +683,8 @@ let decode_inferconfig_to_argv path =
   let one_config_item result (key, json_val) =
     try
       let {decode_json} =
-        IList.find
+        List.find_exn
-          (fun {long; short} ->
+          ~f:(fun {long; short} ->
               String.equal key long
               || (* for deprecated options *) String.equal key short)
           !desc_list in
@@ -704,7 +705,7 @@ let env_var_sep = '^'
 
 let encode_argv_to_env argv =
   String.concat ~sep:(String.make 1 env_var_sep)
-    (IList.filter (fun arg ->
+    (List.filter ~f:(fun arg ->
          not (String.contains arg env_var_sep)
          || (
            warnf "Ignoring unsupported option containing '%c' character: %s@\n"

infer/src/base/Config.ml

@@ -49,7 +49,7 @@ let string_to_analyzer =
    ("bufferoverrun", Bufferoverrun)]
 
 let string_of_analyzer a =
-  IList.find (fun (_, a') -> equal_analyzer a a') string_to_analyzer |> fst
+  List.find_exn ~f:(fun (_, a') -> equal_analyzer a a') string_to_analyzer |> fst
 
 let clang_frontend_action_symbols = [
   ("lint", `Lint);

infer/src/base/IList.ml

@@ -7,16 +7,11 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  *)
 
-type 'a t = 'a list [@@deriving compare]
-
 let exists = List.exists
-let filter = List.filter
-let find = List.find
 let fold_left = List.fold_left
 let fold_left2 = List.fold_left2
 let for_all = List.for_all
 let for_all2 = List.for_all2
-let hd = List.hd
 let iter = List.iter
 let iter2 = List.iter2
 let iteri = List.iteri
@@ -28,7 +23,6 @@ let rev_append = List.rev_append
 let rev_map = List.rev_map
 let sort = List.sort
 let stable_sort = List.stable_sort
-let tl = List.tl
 
 let rec last = function
   | [] -> None
@@ -45,13 +39,6 @@ let fold_lefti (f : 'a -> int -> 'b -> 'a) a l =
   fold_left (fun (i, acc) e -> i +1, f acc i e) (0, a) l
   |> snd
 
-(** tail-recursive variant of List.flatten *)
-let flatten =
-  let rec flatten acc l = match l with
-    | [] -> acc
-    | x:: l' -> flatten (rev_append x acc) l' in
-  fun l -> rev (flatten [] l)
-
 let flatten_options list =
   fold_left (fun list -> function | Some x -> x:: list | None -> list) [] list
   |> rev
@@ -198,17 +185,6 @@ let rec find_map_opt f = function
       then e'
       else find_map_opt f l'
 
-(** Like find_map_opt, but with indices *)
-let find_mapi_opt (f : int -> 'a -> 'b option) l =
-  let rec find_mapi_opt_ f i = function
-    | [] -> None
-    | e :: l' ->
-        let e' = f i e in
-        if e' <> None
-        then e'
-        else find_mapi_opt_ f (i + 1) l' in
-  find_mapi_opt_ f 0 l
-
 let to_string f l =
   let rec aux l =
     match l with
@@ -223,7 +199,7 @@ let mem_assoc equal a l =
 
 (** Like List.assoc but without builtin equality *)
 let assoc equal a l =
-  snd (find (fun x -> equal a (fst x)) l)
+  snd (List.find (fun x -> equal a (fst x)) l)
 
 let range i j =
   let rec aux n acc =

infer/src/base/IList.mli

@@ -7,22 +7,13 @@
  * of patent rights can be found in the PATENTS file in the same directory.
  *)
 
-type 'a t = 'a list [@@deriving compare]
-
-val filter : ('a -> bool) -> 'a list -> 'a list
-
-(** tail-recursive variant of List.flatten *)
-val flatten : 'a list list -> 'a list
-
 (** Remove all None elements from the list. *)
 val flatten_options : ('a option) list -> 'a list
 
-val find : ('a -> bool) -> 'a list -> 'a
 val fold_left : ('a -> 'b -> 'a) -> 'a -> 'b list -> 'a
 val fold_left2 : ('a -> 'b -> 'c -> 'a) -> 'a -> 'b list -> 'c list -> 'a
 val for_all : ('a -> bool) -> 'a list -> bool
 val for_all2 : ('a -> 'b -> bool) -> 'a list -> 'b list -> bool
-val hd : 'a list -> 'a
 val iter : ('a -> unit) -> 'a list -> unit
 val iter2 : ('a -> 'b -> unit) -> 'a list -> 'b list -> unit
 val iteri : (int -> 'a -> unit) -> 'a list -> unit
@@ -54,7 +45,6 @@ val rev_map : ('a -> 'b) -> 'a list -> 'b list
 val sort : ('a -> 'a -> int) -> 'a list -> 'a list
 
 val stable_sort : ('a -> 'a -> int) -> 'a list -> 'a list
-val tl : 'a list -> 'a list
 
 (** last element, if any *)
 val last : 'a list -> 'a option
@@ -95,9 +85,6 @@ val map2 : ('a -> 'b -> 'c) -> 'a list -> 'b list -> 'c list
 (** Return the first non-None result found when applying f to elements of l *)
 val find_map_opt : ('a -> 'b option) -> 'a list -> 'b option
 
-(** Like find_map_opt, but with indices *)
-val find_mapi_opt : (int -> 'a -> 'b option) -> 'a list -> 'b option
-
 val to_string : ('a -> string) -> 'a list -> string
 
 (** Creates an list, inclusive. E.g. `range 2 4` -> [2, 3, 4].

infer/src/base/SourceFile.ml

@@ -128,8 +128,7 @@ let of_header header_file =
   let file_opt = match ext_opt with
     | Some ext when List.mem ~equal:String.equal header_exts ext -> (
         let possible_files = IList.map (fun ext -> file_no_ext ^ "." ^ ext) source_exts in
-        try Some (IList.find path_exists possible_files)
+        List.find ~f:path_exists possible_files
-        with Not_found -> None
       )
     | _ -> None in
   Option.map ~f:from_abs_path file_opt

infer/src/bufferoverrun/arrayBlk.ml

@@ -97,7 +97,7 @@ struct
       let s1 = Itv.get_symbols arr.offset in
       let s2 = Itv.get_symbols arr.size in
       let s3 = Itv.get_symbols arr.stride in
-      IList.flatten [s1; s2; s3]
+      List.concat [s1; s2; s3]
 
   let normalize : t -> t
     = fun arr ->
@@ -176,7 +176,7 @@ let subst : astate -> Itv.Bound.t Itv.SubstMap.t -> astate
 
 let get_symbols : astate -> Itv.Symbol.t list
   = fun a ->
-    IList.flatten (IList.map (fun (_, ai) -> ArrInfo.get_symbols ai) (bindings a))
+    List.concat (IList.map (fun (_, ai) -> ArrInfo.get_symbols ai) (bindings a))
 
 let normalize : astate -> astate
   = fun a -> map ArrInfo.normalize a

infer/src/bufferoverrun/bufferOverrunChecker.ml

@@ -49,7 +49,7 @@ struct
     = fun pname ret params node mem ->
       match ret with
       | Some (id, _) ->
-          let (typ, size) = get_malloc_info (IList.hd params |> fst) in
+          let (typ, size) = get_malloc_info (List.hd_exn params |> fst) in
           let size = Sem.eval size mem (CFG.loc node) |> Dom.Val.get_itv in
           let v = Sem.eval_array_alloc pname node typ Itv.zero size 0 1 in
           Dom.Mem.add_stack (Loc.of_id id) v mem
@@ -59,7 +59,7 @@ struct
     : Procname.t -> (Ident.t * Typ.t) option -> (Exp.t * Typ.t) list -> CFG.node
       -> Dom.Mem.t -> Dom.Mem.t
     = fun pname ret params node mem ->
-      model_malloc pname ret (IList.tl params) node mem
+      model_malloc pname ret (List.tl_exn params) node mem
 
   let model_natual_itv : (Ident.t * Typ.t) option -> Dom.Mem.t -> Dom.Mem.t
     = fun ret mem ->

infer/src/bufferoverrun/bufferOverrunDomain.ml

@@ -491,7 +491,7 @@ struct
 
   let get_symbols : astate -> Itv.Symbol.t list
     = fun mem ->
-      IList.flatten (IList.map (fun (_, v) -> Val.get_symbols v) (bindings mem))
+      List.concat (IList.map (fun (_, v) -> Val.get_symbols v) (bindings mem))
 
   let get_return : astate -> Val.t
     = fun mem ->

infer/src/checkers/BoundedCallTree.ml

@@ -122,19 +122,19 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
                 failwith "Proc type not supported by crashcontext: block" in
           String.equal frame.Stacktrace.method_str (Procname.get_method caller) &&
           matches_class caller in
-        let all_frames = IList.flatten
+        let all_frames = List.concat
             (IList.map (fun trace -> trace.Stacktrace.frames) traces) in
         begin
-          try
+          match List.find ~f:matches_proc all_frames with
-            let frame = IList.find matches_proc all_frames in
+          | Some frame ->
               let new_astate = Domain.add pn astate in
               if Stacktrace.frame_matches_location frame loc then begin
                 let pdesc = proc_data.ProcData.pdesc in
                 output_json_summary pdesc new_astate loc "call_site" get_proc_desc
               end;
               new_astate
-          with
+          | None ->
-            Not_found -> astate
+              astate
         end
     | Sil.Call _ ->
         (* We currently ignore calls through function pointers in C and

infer/src/checkers/SimpleChecker.ml

@@ -90,8 +90,8 @@ module Make (Spec : Spec) : S = struct
       then
         (* should never fail since keys in the invariant map should always be real node id's *)
         let node =
-          IList.find
+          List.find_exn
-            (fun node -> Procdesc.Node.equal_id node_id (Procdesc.Node.get_id node))
+            ~f:(fun node -> Procdesc.Node.equal_id node_id (Procdesc.Node.get_id node))
             nodes in
         Domain.iter
           (fun astate ->

infer/src/checkers/Siof.ml

@@ -47,7 +47,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
       && not (Pvar.is_compile_constant pv)
       && not (is_compile_time_constructed pdesc pv) in
     let globals_accesses =
-      Exp.get_vars e |> snd |> IList.filter is_dangerous_global
+      Exp.get_vars e |> snd |> List.filter ~f:is_dangerous_global
       |> IList.map (fun v -> (v, loc)) in
     GlobalsAccesses.of_list globals_accesses
 
@@ -154,7 +154,7 @@ let report_siof trace pdesc gname loc =
       path in
 
   SiofTrace.get_reportable_sink_paths trace ~trace_of_pname
-  |> IList.filter has_foreign_sink
+  |> List.filter ~f:has_foreign_sink
   |> IList.iter report_one_path
 
 let siof_check pdesc gname = function

infer/src/checkers/Stacktrace.ml

@@ -101,7 +101,7 @@ let of_json filename json =
     Yojson.Basic.Util.to_list (extract_json_member frames_key)
     |> IList.map Yojson.Basic.Util.to_string
     |> IList.map String.strip
-    |> IList.filter (fun s -> s <> "")
+    |> List.filter ~f:(fun s -> s <> "")
     |> IList.map parse_stack_frame in
   make exception_name frames
 

infer/src/checkers/ThreadSafety.ml

@@ -152,7 +152,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
     let truncate = function
       | base, []
       | base, _ :: [] -> base, []
-      | base, accesses -> base, IList.rev (IList.tl (IList.rev accesses)) in
+      | base, accesses -> base, IList.rev (List.tl_exn (IList.rev accesses)) in
 
     (* we don't want to warn on writes to the field if it is (a) thread-confined, or (b) volatile *)
     let is_safe_write access_path tenv =
@@ -714,8 +714,8 @@ let report_thread_safety_violations ( _, tenv, pname, pdesc) trace =
     let pp_accesses fmt sink =
       let _, accesses = PathDomain.Sink.kind sink in
       AccessPath.pp_access_list fmt accesses in
-    let initial_sink, _ = IList.hd (IList.rev sinks) in
+    let initial_sink, _ = List.last_exn sinks in
-    let final_sink, _ = IList.hd sinks in
+    let final_sink, _ = List.hd_exn sinks in
     let initial_sink_site = PathDomain.Sink.call_site initial_sink in
     let final_sink_site = PathDomain.Sink.call_site final_sink in
     let desc_of_sink sink =

infer/src/checkers/Trace.ml

@@ -104,8 +104,8 @@ module Expander (TraceElem : TraceElem.S) = struct
         CallSite.Set.mem (TraceElem.call_site callee_elem) seen in
       (* find sinks that are the same kind as the caller, but have a different procname *)
       let matching_elems =
-        IList.filter
+        List.filter
-          (fun callee_elem ->
+          ~f:(fun callee_elem ->
               [%compare.equal : TraceElem.Kind.t] (TraceElem.kind callee_elem) elem_kind &&
               not (is_recursive callee_elem seen_acc'))
           elems in
@@ -208,8 +208,8 @@ module Make (Spec : Spec) = struct
     let pp_sources = pp_elems Source.call_site in
     let pp_sinks = pp_elems Sink.call_site in
 
-    let original_source = fst (IList.hd sources_passthroughs) in
+    let original_source = fst (List.hd_exn sources_passthroughs) in
-    let final_sink = fst (IList.hd sinks_passthroughs) in
+    let final_sink = fst (List.hd_exn sinks_passthroughs) in
     F.fprintf
       fmt
       "Error: %a -> %a. Full trace:@.%a@.Current procedure %a %a@.%a"

infer/src/checkers/annotations.ml

@@ -86,8 +86,8 @@ let ia_contains ia ann_name =
   List.exists ~f:(class_name_matches ann_name) ia
 
 let ia_get ia ann_name =
-  try Some (fst (IList.find (class_name_matches ann_name) ia))
+  List.find ~f:(class_name_matches ann_name) ia |>
-  with Not_found -> None
+  Option.map ~f:fst
 
 let pdesc_has_parameter_annot pdesc predicate =
   let _, param_annotations = (Procdesc.get_attributes pdesc).ProcAttributes.method_annotation in

infer/src/checkers/checkDeadCode.ml

@@ -75,8 +75,8 @@ let check_final_state tenv proc_name proc_desc final_s =
   if tot_nodes <> tot_visited then
     begin
       let not_visited =
-        IList.filter
+        List.filter
-          (fun n -> not (Procdesc.NodeSet.mem n (State.get_visited final_s)))
+          ~f:(fun n -> not (Procdesc.NodeSet.mem n (State.get_visited final_s)))
           proc_nodes in
       let do_node n =
         let loc = Procdesc.Node.get_loc n in

infer/src/checkers/checkTraceCallSequence.ml

@@ -122,7 +122,7 @@ module State = struct
   (** Map a function to the elements of the set, and filter out inconsistencies. *)
   let map2 (f : Elem.t -> Elem.t list) (s : t) : t =
     let l = ElemSet.elements s in
-    let l' = IList.filter Elem.is_consistent (IList.flatten (IList.map f l)) in
+    let l' = List.filter ~f:Elem.is_consistent (List.concat (IList.map f l)) in
     IList.fold_right ElemSet.add l' ElemSet.empty
 
   let map (f : Elem.t -> Elem.t) s =

infer/src/checkers/checkers.ml

@@ -220,7 +220,7 @@ let callback_check_write_to_parcel_java
     match typ with
     | Typ.Tptr (Tstruct name, _) -> (
         match Tenv.lookup tenv name with
-        | Some { methods } -> IList.filter is_parcel_constructor methods
+        | Some { methods } -> List.filter ~f:is_parcel_constructor methods
         | None -> []
       )
     | _ -> [] in
@@ -261,11 +261,11 @@ let callback_check_write_to_parcel_java
 
     let r_call_descs =
       IList.map node_to_call_desc
-        (IList.filter is_serialization_node
+        (List.filter ~f:is_serialization_node
            (Procdesc.get_sliced_slope r_desc is_serialization_node)) in
     let w_call_descs =
       IList.map node_to_call_desc
-        (IList.filter is_serialization_node
+        (List.filter ~f:is_serialization_node
            (Procdesc.get_sliced_slope w_desc is_serialization_node)) in
 
     let rec check_match = function
@@ -332,7 +332,7 @@ let callback_monitor_nullcheck { Callbacks.proc_desc; idenv; proc_name } =
         | Typ.Tstruct _ -> true
         | Typ.Tptr (Typ.Tstruct _, _) -> true
         | _ -> false in
-      IList.filter is_class_type formals in
+      List.filter ~f:is_class_type formals in
     IList.map fst class_formals) in
   let equal_formal_param exp formal_name = match exp with
     | Exp.Lvar pvar ->
@@ -368,7 +368,7 @@ let callback_monitor_nullcheck { Callbacks.proc_desc; idenv; proc_name } =
       begin
         let was_not_found formal_name =
           not (Exp.Set.exists (fun exp -> equal_formal_param exp formal_name) !checks_to_formals) in
-        let missing = IList.filter was_not_found formal_names in
+        let missing = List.filter ~f:was_not_found formal_names in
         let loc = Procdesc.get_loc proc_desc in
         let pp_file_loc fmt () =
           F.fprintf fmt "%a:%d" SourceFile.pp loc.Location.file loc.Location.line in
@@ -420,18 +420,15 @@ let callback_find_deserialization { Callbacks.proc_desc; get_proc_desc; idenv; p
   let reverse_find_instr f node =
     (* this is not really sound but for the moment a sufficient approximation *)
     let has_instr node =
-      try ignore(IList.find f (Procdesc.Node.get_instrs node)); true
+      List.exists ~f (Procdesc.Node.get_instrs node) in
-      with Not_found -> false in
     let preds =
       Procdesc.Node.get_generated_slope
         node
         (fun n -> Procdesc.Node.get_sliced_preds n has_instr) in
     let instrs =
-      IList.flatten
+      List.concat
         (IList.map (fun n -> IList.rev (Procdesc.Node.get_instrs n)) preds) in
-    try
+    List.find ~f instrs in
-      Some (IList.find f instrs)
-    with Not_found -> None in
 
   let get_return_const proc_name' =
     try

infer/src/checkers/fragmentRetainsViewChecker.ml

@@ -39,7 +39,7 @@ let callback_fragment_retains_view_java
       match Tenv.lookup tenv class_typename with
       | Some { fields } when AndroidFramework.is_fragment tenv class_typename ->
           let declared_view_fields =
-            IList.filter (is_declared_view_typ class_typename) fields in
+            List.filter ~f:(is_declared_view_typ class_typename) fields in
           let fields_nullified = PatternMatch.get_fields_nullified proc_desc in
           (* report if a field is declared by C, but not nulled out in C.onDestroyView *)
           IList.iter

infer/src/checkers/patternMatch.ml

@@ -48,7 +48,7 @@ let rec supertype_find_map_opt tenv f name =
   | Some ({supers} as struct_typ) ->
       begin
         match f name struct_typ with
-        | None -> IList.find_map_opt (supertype_find_map_opt tenv f) supers
+        | None -> List.find_map ~f:(supertype_find_map_opt tenv f) supers
         | result -> result
       end
   | None ->
@@ -134,9 +134,11 @@ 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.equal_fieldname fn fieldname) fields with
+          match List.find
-          | _, ft, _ -> Some (get_type_name ft)
+                  ~f:(function | (fn, _, _) -> Ident.equal_fieldname fn fieldname)
-          | exception Not_found -> None
+                  fields with
+          | Some (_, ft, _) -> Some (get_type_name ft)
+          | None -> None
         )
       | None -> None
     )
@@ -405,7 +407,7 @@ let check_current_class_attributes check tenv = function
 let rec find_superclasses_with_attributes check tenv tname =
   match Tenv.lookup tenv tname with
   | Some (struct_typ) ->
-      let result_from_supers = IList.flatten
+      let result_from_supers = List.concat
           (IList.map (find_superclasses_with_attributes check tenv) struct_typ.supers)
       in
       if check struct_typ.annots then

infer/src/checkers/printfArgs.ml

@@ -46,12 +46,9 @@ let add_printf_like_function plf =
 
 let printf_like_function
     (proc_name: Procname.t): printf_signature option =
-  try
+  List.find
-    Some (
+    ~f:(fun printf -> String.equal printf.unique_id (Procname.to_unique_id proc_name))
-      IList.find
+    !printf_like_functions
-        (fun printf -> String.equal printf.unique_id (Procname.to_unique_id proc_name))
-        !printf_like_functions)
-  with Not_found -> None
 
 let default_format_type_name
     (format_type: string): string =

infer/src/clang/CType_decl.ml

@@ -128,7 +128,7 @@ let get_translate_as_friend_decl decl_list =
         let named_decl_tuple_opt = Clang_ast_proj.get_named_decl_tuple decl in
         Option.value_map ~f:is_translate_as_friend_name ~default:false named_decl_tuple_opt
     | None -> false in
-  match get_friend_decl_opt (IList.find is_translate_as_friend_decl decl_list) with
+  match get_friend_decl_opt (List.find_exn ~f:is_translate_as_friend_decl decl_list) with
   | Some (Clang_ast_t.ClassTemplateSpecializationDecl (_, _, _, _, _, _, _, _, [`Type t_ptr])) ->
       Some t_ptr
   | _ -> None
@@ -150,7 +150,7 @@ let rec get_struct_fields tenv decl =
     | _ -> [] in
   let base_decls = get_superclass_decls decl in
   let base_class_fields = IList.map (get_struct_fields tenv) base_decls in
-  IList.flatten (base_class_fields @ (IList.map do_one_decl decl_list))
+  List.concat (base_class_fields @ (IList.map do_one_decl decl_list))
 
 (* For a record declaration it returns/constructs the type *)
 and get_record_declaration_type tenv decl =

infer/src/clang/ComponentKit.ml

@@ -233,14 +233,14 @@ let component_with_multiple_factory_methods_advice context an =
     let attrs = match decl with
       | ObjCMethodDecl (decl_info, _, _) -> decl_info.Clang_ast_t.di_attributes
       | _ -> assert false in
-    let unavailable_attrs = (IList.filter is_unavailable_attr attrs) in
+    let unavailable_attrs = (List.filter ~f:is_unavailable_attr attrs) 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 =
     match if_decl with
     | Clang_ast_t.ObjCInterfaceDecl (_, _, decls, _, _) ->
-        let factory_methods = IList.filter (is_available_factory_method if_decl) decls in
+        let factory_methods = List.filter ~f:(is_available_factory_method if_decl) decls in
         CTL.True, IList.map (fun meth_decl -> {
               CIssue.name = "COMPONENT_WITH_MULTIPLE_FACTORY_METHODS";
               severity = Exceptions.Kadvice;
@@ -290,7 +290,7 @@ let rec _component_initializer_with_side_effects_advice
     | Clang_ast_t.DeclRefExpr (_, _, _, decl_ref_expr_info) ->
         let refs = [decl_ref_expr_info.drti_decl_ref;
                     decl_ref_expr_info.drti_found_decl_ref] in
-        (match IList.find_map_opt CAst_utils.name_of_decl_ref_opt refs with
+        (match List.find_map ~f:CAst_utils.name_of_decl_ref_opt refs with
          | Some "dispatch_after"
          | Some "dispatch_async"
          | Some "dispatch_sync" ->

infer/src/clang/cFrontend_checkers_main.ml

@@ -214,7 +214,7 @@ let do_frontend_checks trans_unit_ctx ast =
         let is_decl_allowed decl =
           let decl_info = Clang_ast_proj.get_decl_tuple decl in
           CLocation.should_do_frontend_check trans_unit_ctx decl_info.Clang_ast_t.di_source_range in
-        let allowed_decls = IList.filter is_decl_allowed decl_list in
+        let allowed_decls = List.filter ~f:is_decl_allowed decl_list in
         (* We analyze the top level and then all the allowed declarations *)
         CFrontend_errors.invoke_set_of_checkers_on_node context (Ctl_parser_types.Decl ast);
         IList.iter (do_frontend_checks_decl context) allowed_decls;

infer/src/clang/cMethod_trans.ml

@@ -151,7 +151,7 @@ let get_assume_not_null_calls param_decls =
             decl_info name qt.Clang_ast_t.qt_type_ptr in
         [(`ClangStmt assume_call)]
     | _ -> [] in
-  IList.flatten (IList.map do_one_param param_decls)
+  List.concat (IList.map do_one_param param_decls)
 
 let get_init_list_instrs method_decl_info =
   let create_custom_instr construct_instr = `CXXConstructorInit construct_instr in

infer/src/clang/cTrans.ml

@@ -168,10 +168,10 @@ struct
     (f exps, !insts)
 
   let collect_exprs res_trans_list =
-    IList.flatten (IList.map (fun res_trans -> res_trans.exps) res_trans_list)
+    List.concat (IList.map (fun res_trans -> res_trans.exps) res_trans_list)
 
   let collect_initid_exprs res_trans_list =
-    IList.flatten (IList.map (fun res_trans -> res_trans.initd_exps) res_trans_list)
+    List.concat (IList.map (fun res_trans -> res_trans.initd_exps) res_trans_list)
 
   (* If e is a block and the calling node has the priority then *)
   (* we need to release the priority to allow*)
@@ -443,7 +443,7 @@ struct
       let open Clang_ast_t in
       let decl_info = Clang_ast_proj.get_decl_tuple decl in
       let get_attr_opt = function DeprecatedAttr a -> Some a | _ -> None in
-      match IList.find_map_opt get_attr_opt decl_info.di_attributes with
+      match List.find_map ~f:get_attr_opt decl_info.di_attributes with
       | Some attribute_info ->
           (match attribute_info.ai_parameters with
            | [_; arg; _; _; _; _] -> Some arg
@@ -888,7 +888,7 @@ struct
           Option.value_map
             ~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
+          let params = List.tl_exn (collect_exprs result_trans_subexprs) in
           if Int.equal (IList.length params) (IList.length params_stmt) then
             params
           else (Logging.err_debug
@@ -929,7 +929,7 @@ struct
     let sil_loc = CLocation.get_sil_location si context in
     (* first for method address, second for 'this' expression *)
     assert (Int.equal (IList.length result_trans_callee.exps) 2);
-    let (sil_method, _) = IList.hd result_trans_callee.exps in
+    let (sil_method, _) = List.hd_exn result_trans_callee.exps in
     let callee_pname =
       match sil_method with
       | Exp.Const (Const.Cfun pn) -> pn
@@ -944,7 +944,7 @@ struct
       let res_trans_p = IList.map (instruction' trans_state_param) params_stmt in
       result_trans_callee :: res_trans_p in
     (* first expr is method address, rest are params including 'this' parameter *)
-    let actual_params = IList.tl (collect_exprs result_trans_subexprs) in
+    let actual_params = List.tl_exn (collect_exprs result_trans_subexprs) in
     match cxx_method_builtin_trans trans_state_pri sil_loc result_trans_subexprs callee_pname with
     | Some builtin -> builtin
     | _ ->

infer/src/clang/cTrans_utils.ml

@@ -723,7 +723,7 @@ let var_or_zero_in_init_list tenv e typ ~return_zero:return_zero =
               IList.map (fun (fieldname, _, _) -> Exp.Lfield (e, fieldname, typ)) fields in
             let lh_types = IList.map (fun (_, fieldtype, _) -> fieldtype) fields in
             let exp_types = zip lh_exprs lh_types in
-            IList.map (fun (e, t) -> IList.flatten (var_or_zero_in_init_list' e t tns)) exp_types
+            IList.map (fun (e, t) -> List.concat (var_or_zero_in_init_list' e t tns)) exp_types
         | None ->
             assert false
       )
@@ -737,12 +737,12 @@ let var_or_zero_in_init_list tenv e typ ~return_zero:return_zero =
         let lh_types = replicate size arrtyp in
         let exp_types = zip lh_exprs lh_types in
         IList.map (fun (e, t) ->
-            IList.flatten (var_or_zero_in_init_list' e t tns)) exp_types
+            List.concat (var_or_zero_in_init_list' e t tns)) exp_types
     | Typ.Tint _ | Typ.Tfloat _  | Typ.Tptr _ ->
         let exp = if return_zero then Sil.zero_value_of_numerical_type typ else e in
         [ [(exp, typ)] ]
     | Typ.Tfun _ | Typ.Tvoid | Typ.Tarray _ -> assert false in
-  IList.flatten (var_or_zero_in_init_list' e typ String.Set.empty)
+  List.concat (var_or_zero_in_init_list' e typ String.Set.empty)
 
 (*
 (** Similar to extract_item_from_singleton but for option type *)

infer/src/eradicate/eradicate.ml

@@ -232,7 +232,7 @@ struct
           let rec fixpoint initializers_old =
             let initializers_new = get_private_called initializers_old in
             let initializers_new' =
-              IList.filter (fun (pn, _) -> not (Procname.Set.mem pn !seen)) initializers_new in
+              List.filter ~f:(fun (pn, _) -> not (Procname.Set.mem pn !seen)) initializers_new in
             mark_seen initializers_new';
             if initializers_new' <> [] then fixpoint initializers_new' in
 

infer/src/harness/androidFramework.ml

@@ -88,7 +88,7 @@ let get_lifecycle_for_framework_typ_opt tenv lifecycle_typ lifecycle_proc_strs =
   | Some { methods } ->
       (* TODO (t4645631): collect the procedures for which is_java is returning false *)
       let lookup_proc lifecycle_proc =
-        IList.find (fun decl_proc ->
+        List.find_exn ~f:(fun decl_proc ->
             match decl_proc with
             | Procname.Java decl_proc_java ->
                 String.equal lifecycle_proc (Procname.java_get_method decl_proc_java)

infer/src/harness/inhabit.ml

@@ -60,8 +60,8 @@ let create_fresh_local_name () =
   incr local_name_cntr;
   "dummy_local" ^ string_of_int !local_name_cntr
 
-(** more forgiving variation of IList.tl that won't raise an exception on the empty list *)
+(** more forgiving variation of List.tl that won't raise an exception on the empty list *)
-let tl_or_empty l = if List.is_empty l then l else IList.tl l
+let tl_or_empty l = if List.is_empty l then l else List.tl_exn l
 
 let get_non_receiver_formals formals = tl_or_empty formals
 
@@ -106,7 +106,7 @@ let rec inhabit_typ tenv typ cfg env =
                       && IList.for_all (fun (_, typ) ->
                           not (TypSet.mem typ env.cur_inhabiting)
                         ) (try_get_non_receiver_formals p) in
-                    IList.filter (fun p -> is_suitable_constructor p) methods
+                    List.filter ~f:(fun p -> is_suitable_constructor p) methods
                 | _ -> []
               )
             | _ -> []

infer/src/integration/CompilationDatabase.ml

@@ -58,13 +58,13 @@ let decode_json_file (database : t) json_path =
     | `List arguments ->
         IList.iter parse_json arguments
     | `Assoc l ->
-        let dir = match IList.find_map_opt get_dir l with
+        let dir = match List.find_map ~f:get_dir l with
           | Some dir -> dir
           | None -> exit_format_error () in
-        let file = match IList.find_map_opt get_file l with
+        let file = match List.find_map ~f:get_file l with
           | Some file -> file
           | None -> exit_format_error () in
-        let cmd = match IList.find_map_opt get_cmd l with
+        let cmd = match List.find_map ~f:get_cmd l with
           | Some cmd -> cmd
           | None -> exit_format_error () in
         let command, args = parse_command_and_arguments cmd in

infer/src/java/jTrans.ml

@@ -100,20 +100,20 @@ let retrieve_fieldname fieldname =
     if Int.equal (IList.length subs) 0 then
       assert false
     else
-      IList.hd (IList.rev subs)
+      List.hd_exn (IList.rev subs)
   with _ -> assert false
 
 
 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
+    List.find
-      (fun (fieldname, _, _) -> String.equal (retrieve_fieldname fieldname) (JBasics.fs_name fs))
+      ~f:(fun (fieldname, _, _) -> String.equal (retrieve_fieldname fieldname) (JBasics.fs_name fs))
       (if static then statics else fields)
   with
-  | fieldname, _, _ ->
+  | Some (fieldname, _, _) ->
       fieldname
-  | exception Not_found ->
+  | None ->
       (* TODO: understand why fields cannot be found here *)
       L.do_err "cannot find %s.%s@." (JBasics.cn_name cn) (JBasics.fs_name fs);
       raise (Frontend_error "Cannot find fieldname")

infer/src/java/jTransType.ml

@@ -391,14 +391,14 @@ let param_type program tenv cn name vt =
 
 let get_var_type_from_sig (context : JContext.t) var =
   let program = context.program in
-  try
   let tenv = JContext.get_tenv context in
-    let vt', var' =
+  List.find_map ~f:(
-      IList.find
+    fun (vt', var') ->
-        (fun (_, var') -> JBir.var_equal var var')
+      if JBir.var_equal var var'
-        (JBir.params context.impl) in
+      then Some (param_type program tenv context.cn var' vt')
-    Some (param_type program tenv context.cn var' vt')
+      else None
-  with Not_found -> None
+  )
+    (JBir.params context.impl)
 
 
 let get_var_type context var =

infer/src/quandary/JavaTrace.ml

@@ -67,8 +67,8 @@ module SourceKind = struct
                 | None ->
                     (* check the list of externally specified sources *)
                     let procedure = class_name ^ "." ^ method_name in
-                    IList.find_map_opt
+                    List.find_map
-                      (fun (source_spec : QuandaryConfig.Source.t) ->
+                      ~f:(fun (source_spec : QuandaryConfig.Source.t) ->
                           if Str.string_match source_spec.procedure procedure 0
                           then Some (of_string source_spec.kind)
                           else None)
@@ -156,7 +156,7 @@ module SinkKind = struct
       let actuals_to_taint, offset =
         if Procname.java_is_static pname || taint_this
         then actuals, 0
-        else IList.tl actuals, 1 in
+        else List.tl_exn actuals, 1 in
       IList.mapi
         (fun param_num _ -> kind, param_num + offset, report_reachable)
         actuals_to_taint in
@@ -236,8 +236,8 @@ module SinkKind = struct
                 | class_name, method_name ->
                     (* check the list of externally specified sinks *)
                     let procedure = class_name ^ "." ^ method_name in
-                    IList.find_map_opt
+                    List.find_map
-                      (fun (sink_spec : QuandaryConfig.Sink.t) ->
+                      ~f:(fun (sink_spec : QuandaryConfig.Sink.t) ->
                           if Str.string_match sink_spec.procedure procedure 0
                           then
                             let kind = of_string sink_spec.kind in

infer/src/quandary/TaintAnalysis.ml

@@ -168,8 +168,8 @@ module Make (TaintSpecification : TaintSpec.S) = struct
             TraceDomain.empty in
 
       let pp_path_short fmt (_, sources_passthroughs, sinks_passthroughs) =
-        let original_source = fst (IList.hd sources_passthroughs) in
+        let original_source = fst (List.hd_exn sources_passthroughs) in
-        let final_sink = fst (IList.hd sinks_passthroughs) in
+        let final_sink = fst (List.hd_exn sinks_passthroughs) in
         F.fprintf
           fmt
           "%a -> %a"

infer/src/unit/schedulerTests.ml

@@ -39,19 +39,17 @@ module MockProcCfg = struct
   let equal_id = Int.equal
 
   let succs t n =
-    try
     let node_id = id n in
-      IList.find
+    List.find
-        (fun (node, _) -> equal_id (id node) node_id)
+      ~f:(fun (node, _) -> equal_id (id node) node_id)
-        t
+      t |>
-      |> snd
+    Option.value_map ~f:snd ~default:[]
-    with Not_found -> []
 
   let preds t n =
     try
       let node_id = id n in
-      IList.filter
+      List.filter
-        (fun (_, succs) ->
+        ~f:(fun (_, succs) ->
            List.exists ~f:(fun node -> equal_id (id node) node_id) succs)
         t
       |> IList.map fst