diff --git a/infer/src/IR/CallFlags.re b/infer/src/IR/CallFlags.re
new file mode 100644
index 000000000..3ddee7557
--- /dev/null
+++ b/infer/src/IR/CallFlags.re
@@ -0,0 +1,53 @@
+/*
+ * vim: set ft=rust:
+ * vim: set ft=reason:
+ *
+ * Copyright (c) 2009 - 2013 Monoidics ltd.
+ * Copyright (c) 2013 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+open! Utils;
+
+
+/** The Smallfoot Intermediate Language: Call Flags */
+let module L = Logging;
+
+let module F = Format;
+
+
+/** Flags for a procedure call */
+type t = {
+  cf_virtual: bool,
+  cf_interface: bool,
+  cf_noreturn: bool,
+  cf_is_objc_block: bool,
+  cf_targets: list Procname.t
+};
+
+let compare cflag1 cflag2 =>
+  bool_compare cflag1.cf_virtual cflag2.cf_virtual |>
+    next bool_compare cflag1.cf_interface cflag2.cf_interface |>
+    next bool_compare cflag1.cf_noreturn cflag2.cf_noreturn |>
+    next bool_compare cflag1.cf_is_objc_block cflag2.cf_is_objc_block;
+
+let pp f cf => {
+  if cf.cf_virtual {
+    F.fprintf f " virtual"
+  };
+  if cf.cf_noreturn {
+    F.fprintf f " noreturn"
+  }
+};
+
+let default = {
+  cf_virtual: false,
+  cf_interface: false,
+  cf_noreturn: false,
+  cf_is_objc_block: false,
+  cf_targets: []
+};
diff --git a/infer/src/IR/CallFlags.rei b/infer/src/IR/CallFlags.rei
new file mode 100644
index 000000000..0de3632cd
--- /dev/null
+++ b/infer/src/IR/CallFlags.rei
@@ -0,0 +1,38 @@
+/*
+ * vim: set ft=rust:
+ * vim: set ft=reason:
+ *
+ * Copyright (c) 2009 - 2013 Monoidics ltd.
+ * Copyright (c) 2013 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+open! Utils;
+
+
+/** The Smallfoot Intermediate Language: Call Flags */
+let module L = Logging;
+
+let module F = Format;
+
+
+/** Flags for a procedure call */
+type t = {
+  cf_virtual: bool,
+  cf_interface: bool,
+  cf_noreturn: bool,
+  cf_is_objc_block: bool,
+  cf_targets: list Procname.t
+};
+
+let compare: t => t => int;
+
+let pp: F.formatter => t => unit;
+
+
+/** Default value where all fields are set to false */
+let default: t;
diff --git a/infer/src/IR/Cfg.re b/infer/src/IR/Cfg.re
index 4715aad06..ded15ea4a 100644
--- a/infer/src/IR/Cfg.re
+++ b/infer/src/IR/Cfg.re
@@ -704,7 +704,7 @@ let module Node = {
           [(Sil.Var id, _), ...origin_args]
           loc
           call_flags
-          when call_flags.Sil.cf_virtual && redirected_class_name id != None => {
+          when call_flags.CallFlags.cf_virtual && redirected_class_name id != None => {
           let redirected_typ = Option.get (redirected_class_name id);
           let redirected_pname =
             Procname.replace_class
diff --git a/infer/src/IR/Sil.re b/infer/src/IR/Sil.re
index 2e3934f51..8e9c0337d 100644
--- a/infer/src/IR/Sil.re
+++ b/infer/src/IR/Sil.re
@@ -65,24 +65,6 @@ type dangling_kind =
 /** position in a path: proc name, node id */
 type path_pos = (Procname.t, int);
 
-
-/** Flags for a procedure call */
-type call_flags = {
-  cf_virtual: bool,
-  cf_interface: bool,
-  cf_noreturn: bool,
-  cf_is_objc_block: bool,
-  cf_targets: list Procname.t
-};
-
-let cf_default = {
-  cf_virtual: false,
-  cf_interface: false,
-  cf_noreturn: false,
-  cf_is_objc_block: false,
-  cf_targets: []
-};
-
 type taint_kind =
   | Tk_unverified_SSL_socket
   | Tk_shared_preferences_data
@@ -100,14 +82,14 @@ type dexp =
   | Dconst of Const.t
   | Dsizeof of Typ.t (option dexp) Subtype.t
   | Dderef of dexp
-  | Dfcall of dexp (list dexp) Location.t call_flags
+  | Dfcall of dexp (list dexp) Location.t CallFlags.t
   | Darrow of dexp Ident.fieldname
   | Ddot of dexp Ident.fieldname
   | Dpvar of Pvar.t
   | Dpvaraddr of Pvar.t
   | Dunop of Unop.t dexp
   | Dunknown
-  | Dretcall of dexp (list dexp) Location.t call_flags;
+  | Dretcall of dexp (list dexp) Location.t CallFlags.t;
 
 
 /** Value paths: identify an occurrence of a value in a symbolic heap
@@ -213,7 +195,7 @@ type instr =
   /** [Call (ret_id1..ret_idn, e_fun, arg_ts, loc, call_flags)] represents an instructions
       [ret_id1..ret_idn = e_fun(arg_ts);]
       where n = 0 for void return and n > 1 for struct return */
-  | Call of (list Ident.t) exp (list (exp, Typ.t)) Location.t call_flags
+  | Call of (list Ident.t) exp (list (exp, Typ.t)) Location.t CallFlags.t
   /** nullify stack variable */
   | Nullify of Pvar.t Location.t
   | Abstract of Location.t /** apply abstraction */
@@ -1363,17 +1345,6 @@ let instr_get_exps =
   | Declare_locals _ => [];
 
 
-/** Pretty print call flags */
-let pp_call_flags f cf => {
-  if cf.cf_virtual {
-    F.fprintf f " virtual"
-  };
-  if cf.cf_noreturn {
-    F.fprintf f " noreturn"
-  }
-};
-
-
 /** Pretty print an instruction. */
 let pp_instr pe0 f instr => {
   let (pe, changed) = color_pre_wrapper pe0 f instr;
@@ -1396,7 +1367,7 @@ let pp_instr pe0 f instr => {
       e
       (pp_comma_seq (pp_exp_typ pe))
       arg_ts
-      pp_call_flags
+      CallFlags.pp
       cf
       Location.pp
       loc
@@ -2995,12 +2966,6 @@ let instr_sub_ids sub_id_binders::sub_id_binders (f: Ident.t => exp) instr => {
 /** apply [subst] to all id's in [instr], including binder id's */
 let instr_sub (subst: subst) instr => instr_sub_ids sub_id_binders::true (apply_sub subst) instr;
 
-let call_flags_compare cflag1 cflag2 =>
-  bool_compare cflag1.cf_virtual cflag2.cf_virtual |>
-    next bool_compare cflag1.cf_interface cflag2.cf_interface |>
-    next bool_compare cflag1.cf_noreturn cflag2.cf_noreturn |>
-    next bool_compare cflag1.cf_is_objc_block cflag2.cf_is_objc_block;
-
 let exp_typ_compare (exp1, typ1) (exp2, typ2) => {
   let n = exp_compare exp1 exp2;
   if (n != 0) {
@@ -3086,7 +3051,7 @@ let instr_compare instr1 instr2 =>
           if (n != 0) {
             n
           } else {
-            call_flags_compare cf1 cf2
+            CallFlags.compare cf1 cf2
           }
         }
       }
@@ -3332,7 +3297,7 @@ let instr_compare_structural instr1 instr2 exp_map => {
           if (n != 0) {
             n
           } else {
-            call_flags_compare cf1 cf2
+            CallFlags.compare cf1 cf2
           },
           exp_map
         )
diff --git a/infer/src/IR/Sil.rei b/infer/src/IR/Sil.rei
index 705649cad..2ea625edd 100644
--- a/infer/src/IR/Sil.rei
+++ b/infer/src/IR/Sil.rei
@@ -53,20 +53,6 @@ type dangling_kind =
 /** position in a path: proc name, node id */
 type path_pos = (Procname.t, int);
 
-
-/** Flags for a procedure call */
-type call_flags = {
-  cf_virtual: bool,
-  cf_interface: bool,
-  cf_noreturn: bool,
-  cf_is_objc_block: bool,
-  cf_targets: list Procname.t
-};
-
-
-/** Default value for call_flags where all fields are set to false */
-let cf_default: call_flags;
-
 type taint_kind =
   | Tk_unverified_SSL_socket
   | Tk_shared_preferences_data
@@ -84,14 +70,14 @@ type dexp =
   | Dconst of Const.t
   | Dsizeof of Typ.t (option dexp) Subtype.t
   | Dderef of dexp
-  | Dfcall of dexp (list dexp) Location.t call_flags
+  | Dfcall of dexp (list dexp) Location.t CallFlags.t
   | Darrow of dexp Ident.fieldname
   | Ddot of dexp Ident.fieldname
   | Dpvar of Pvar.t
   | Dpvaraddr of Pvar.t
   | Dunop of Unop.t dexp
   | Dunknown
-  | Dretcall of dexp (list dexp) Location.t call_flags;
+  | Dretcall of dexp (list dexp) Location.t CallFlags.t;
 
 
 /** Value paths: identify an occurrence of a value in a symbolic heap
@@ -213,7 +199,7 @@ type instr =
   /** [Call (ret_id1..ret_idn, e_fun, arg_ts, loc, call_flags)] represents an instructions
       [ret_id1..ret_idn = e_fun(arg_ts);]
       where n = 0 for void return and n > 1 for struct return */
-  | Call of (list Ident.t) exp (list (exp, Typ.t)) Location.t call_flags
+  | Call of (list Ident.t) exp (list (exp, Typ.t)) Location.t CallFlags.t
   /** nullify stack variable */
   | Nullify of Pvar.t Location.t
   | Abstract of Location.t /** apply abstraction */
@@ -472,8 +458,6 @@ let exp_equal: exp => exp => bool;
 /** exp_is_array_index_of index arr returns true is index is an array index of arr. */
 let exp_is_array_index_of: exp => exp => bool;
 
-let call_flags_compare: call_flags => call_flags => int;
-
 let exp_typ_compare: (exp, Typ.t) => (exp, Typ.t) => int;
 
 let instr_compare: instr => instr => int;
diff --git a/infer/src/backend/errdesc.ml b/infer/src/backend/errdesc.ml
index 717de68ed..437106cda 100644
--- a/infer/src/backend/errdesc.ml
+++ b/infer/src/backend/errdesc.ml
@@ -145,7 +145,7 @@ let id_is_assigned_then_dead node id =
     and return the function name and arguments *)
 let find_normal_variable_funcall
     (node: Cfg.Node.t)
-    (id: Ident.t): (Sil.exp * (Sil.exp list) * Location.t * Sil.call_flags) option =
+    (id: Ident.t): (Sil.exp * (Sil.exp list) * Location.t * CallFlags.t) option =
   let find_declaration _ = function
     | Sil.Call ([id0], fun_exp, args, loc, call_flags) when Ident.equal id id0 ->
         Some (fun_exp, IList.map fst args, loc, call_flags)
diff --git a/infer/src/backend/errdesc.mli b/infer/src/backend/errdesc.mli
index 8fb453eb6..92359ec6d 100644
--- a/infer/src/backend/errdesc.mli
+++ b/infer/src/backend/errdesc.mli
@@ -25,7 +25,7 @@ val hpred_is_open_resource : 'a Prop.t -> Sil.hpred -> Sil.resource option
 (** Find the function call instruction used to initialize normal variable [id],
     and return the function name and arguments *)
 val find_normal_variable_funcall :
-  Cfg.Node.t -> Ident.t -> (Sil.exp * (Sil.exp list) * Location.t * Sil.call_flags) option
+  Cfg.Node.t -> Ident.t -> (Sil.exp * (Sil.exp list) * Location.t * CallFlags.t) option
 
 (** Find a program variable assignment in the current node or straightline predecessor. *)
 val find_program_variable_assignment : Cfg.Node.t -> Pvar.t -> (Cfg.Node.t * Ident.t) option
diff --git a/infer/src/backend/modelBuiltins.ml b/infer/src/backend/modelBuiltins.ml
index 26983930d..67bb900d9 100644
--- a/infer/src/backend/modelBuiltins.ml
+++ b/infer/src/backend/modelBuiltins.ml
@@ -1165,7 +1165,8 @@ let execute_objc_alloc_no_fail
     | Some pname -> [Sil.Const (Const.Cfun pname), Typ.Tvoid]
     | None -> [] in
   let alloc_instr =
-    Sil.Call (ret_ids, alloc_fun, [(sizeof_typ, ptr_typ)] @ alloc_fun_exp, loc, Sil.cf_default) in
+    Sil.Call
+      (ret_ids, alloc_fun, [(sizeof_typ, ptr_typ)] @ alloc_fun_exp, loc, CallFlags.default) in
   SymExec.instrs tenv pdesc [alloc_instr] symb_state
 
 let mk_objc_class_method class_name method_name =
diff --git a/infer/src/backend/preanal.ml b/infer/src/backend/preanal.ml
index 69276f9df..68c2c9b46 100644
--- a/infer/src/backend/preanal.ml
+++ b/infer/src/backend/preanal.ml
@@ -16,8 +16,8 @@ let add_dispatch_calls pdesc cg tenv =
     (* TODO: handle dynamic dispatch for virtual calls as well *)
     let call_flags_is_dispatch call_flags =
       (* if sound dispatch is turned off, only consider dispatch for interface calls *)
-      (Config.sound_dynamic_dispatch && call_flags.Sil.cf_virtual) ||
-      call_flags.Sil.cf_interface in
+      (Config.sound_dynamic_dispatch && call_flags.CallFlags.cf_virtual) ||
+      call_flags.CallFlags.cf_interface in
     let instr_is_dispatch_call = function
       | Sil.Call (_, _, _, _, call_flags) -> call_flags_is_dispatch call_flags
       | _ -> false in
@@ -28,7 +28,7 @@ let add_dispatch_calls pdesc cg tenv =
                   (((_, receiver_typ) :: _) as args), loc, call_flags) as instr
         when call_flags_is_dispatch call_flags ->
           (* the frontend should not populate the list of targets *)
-          assert (call_flags.Sil.cf_targets = []);
+          assert (call_flags.CallFlags.cf_targets = []);
           let receiver_typ_no_ptr = match receiver_typ with
             | Typ.Tptr (typ', _) ->
                 typ'
@@ -49,7 +49,7 @@ let add_dispatch_calls pdesc cg tenv =
                IList.iter
                  (fun target_pname -> Cg.add_edge cg caller_pname target_pname)
                  targets_to_add;
-               let call_flags' = { call_flags with Sil.cf_targets = targets_to_add; } in
+               let call_flags' = { call_flags with CallFlags.cf_targets = targets_to_add; } in
                Sil.Call (ret_ids, call_exp, args, loc, call_flags')
            | [] -> instr)
 
diff --git a/infer/src/backend/symExec.ml b/infer/src/backend/symExec.ml
index e4b24f2d4..0daa3344b 100644
--- a/infer/src/backend/symExec.ml
+++ b/infer/src/backend/symExec.ml
@@ -566,7 +566,7 @@ let resolve_virtual_pname tenv prop actuals callee_pname call_flags : Procname.t
     then resolve receiver_exp called_pname prop
     else called_pname in
   match actuals with
-  | _ when not (call_flags.Sil.cf_virtual || call_flags.Sil.cf_interface) ->
+  | _ when not (call_flags.CallFlags.cf_virtual || call_flags.CallFlags.cf_interface) ->
       (* if this is not a virtual or interface call, there's no need for resolution *)
       [callee_pname]
   | (receiver_exp, actual_receiver_typ) :: _ ->
@@ -575,13 +575,13 @@ let resolve_virtual_pname tenv prop actuals callee_pname call_flags : Procname.t
         [do_resolve callee_pname receiver_exp actual_receiver_typ]
       else if Config.sound_dynamic_dispatch then
         let targets =
-          if call_flags.Sil.cf_virtual
+          if call_flags.CallFlags.cf_virtual
           then
             (* virtual call--either [called_pname] or an override in some subtype may be called *)
-            callee_pname :: call_flags.Sil.cf_targets
+            callee_pname :: call_flags.CallFlags.cf_targets
           else
             (* interface call--[called_pname] has no implementation), we don't want to consider *)
-            call_flags.Sil.cf_targets in (* interface call, don't want to consider *)
+            call_flags.CallFlags.cf_targets in (* interface call, don't want to consider *)
         (* return true if (receiver typ of [target_pname]) <: [actual_receiver_typ] *)
         let may_dispatch_to target_pname =
           let target_receiver_typ = get_receiver_typ target_pname actual_receiver_typ in
@@ -594,8 +594,8 @@ let resolve_virtual_pname tenv prop actuals callee_pname call_flags : Procname.t
         else resolved_pname :: feasible_targets
       else
         begin
-          match call_flags.Sil.cf_targets with
-          | target :: _ when call_flags.Sil.cf_interface &&
+          match call_flags.CallFlags.cf_targets with
+          | target :: _ when call_flags.CallFlags.cf_interface &&
                              receiver_types_equal callee_pname actual_receiver_typ ->
               (* "production mode" of dynamic dispatch for Java: unsound, but faster. the handling
                  is restricted to interfaces: if we can't resolve an interface call, we pick the
@@ -628,7 +628,7 @@ let resolve_java_pname tenv prop args pname_java call_flags : Procname.java =
     match args with
     | [] ->
         pname_java, []
-    | (first_arg, _) :: other_args when call_flags.Sil.cf_virtual ->
+    | (first_arg, _) :: other_args when call_flags.CallFlags.cf_virtual ->
         let resolved =
           begin
             match resolve_typename prop first_arg with
@@ -1222,10 +1222,10 @@ let rec sym_exec tenv current_pdesc _instr (prop_: Prop.normal Prop.t) path
       IList.flatten (IList.map do_call sentinel_result)
   | Sil.Call (ret_ids, fun_exp, actual_params, loc, call_flags) -> (** Call via function pointer *)
       let (prop_r, n_actual_params) = normalize_params current_pname prop_ actual_params in
-      if call_flags.Sil.cf_is_objc_block then
+      if call_flags.CallFlags.cf_is_objc_block then
         Rearrange.check_call_to_objc_block_error current_pdesc prop_r fun_exp loc;
       Rearrange.check_dereference_error current_pdesc prop_r fun_exp loc;
-      if call_flags.Sil.cf_noreturn then begin
+      if call_flags.CallFlags.cf_noreturn then begin
         L.d_str "Unknown function pointer with noreturn attribute ";
         Sil.d_exp fun_exp; L.d_strln ", diverging.";
         diverge prop_r path
@@ -1424,7 +1424,7 @@ and unknown_or_scan_call ~is_scan ret_type_option ret_annots
       IList.fold_left do_attribute p (Prop.get_exp_attributes p e) in
     let filtered_args =
       match args, instr with
-      | _:: other_args, Sil.Call (_, _, _, _, { Sil.cf_virtual }) when cf_virtual ->
+      | _:: other_args, Sil.Call (_, _, _, _, { CallFlags.cf_virtual }) when cf_virtual ->
           (* Do not remove the file attribute on the reciver for virtual calls *)
           other_args
       | _ -> args in
diff --git a/infer/src/checkers/codeQuery.ml b/infer/src/checkers/codeQuery.ml
index 238ee6166..bc33714eb 100644
--- a/infer/src/checkers/codeQuery.ml
+++ b/infer/src/checkers/codeQuery.ml
@@ -170,7 +170,8 @@ module Match = struct
         else false
     | CodeQueryAst.Call _, _ -> false
     | CodeQueryAst.MethodCall (ae1, ae2, ael_opt),
-      Sil.Call (_, Sil.Const (Const.Cfun pn), (_e1, _):: params, loc, { Sil.cf_virtual = true }) ->
+      Sil.Call (_, Sil.Const (Const.Cfun pn), (_e1, _) :: params,
+                loc, { CallFlags.cf_virtual = true }) ->
         let e1 = Idenv.expand_expr idenv _e1 in
         let vl = IList.map (function _e, _ -> Vval (Idenv.expand_expr idenv _e)) params in
         if exp_match env ae1 (Vval e1) && exp_match env ae2 (Vfun pn) && opt_match exp_list_match env ael_opt vl then
diff --git a/infer/src/checkers/repeatedCallsChecker.ml b/infer/src/checkers/repeatedCallsChecker.ml
index 5acadc457..4d684b110 100644
--- a/infer/src/checkers/repeatedCallsChecker.ml
+++ b/infer/src/checkers/repeatedCallsChecker.ml
@@ -29,7 +29,7 @@ struct
             (* ignore return ids and call flags *)
             let n = Sil.exp_compare e1 e2 in
             if n <> 0 then n else let n = IList.compare Sil.exp_typ_compare etl1 etl2 in
-              if n <> 0 then n else Sil.call_flags_compare cf1 cf2
+              if n <> 0 then n else CallFlags.compare cf1 cf2
         | _ -> Sil.instr_compare i1 i2
     end)
 
diff --git a/infer/src/clang/cArithmetic_trans.ml b/infer/src/clang/cArithmetic_trans.ml
index d04e997bd..cbea96f1e 100644
--- a/infer/src/clang/cArithmetic_trans.ml
+++ b/infer/src/clang/cArithmetic_trans.ml
@@ -27,7 +27,7 @@ let assignment_arc_mode e1 typ e2 loc rhs_owning_method is_e1_decl =
   let autorelease_pname = ModelBuiltins.__set_autorelease_attribute in
   let mk_call procname e t =
     let bi_retain = Sil.Const (Const.Cfun procname) in
-    Sil.Call([], bi_retain, [(e, t)], loc, Sil.cf_default) in
+    Sil.Call([], bi_retain, [(e, t)], loc, CallFlags.default) in
   match typ with
   | Typ.Tptr (_, Typ.Pk_pointer) when not rhs_owning_method && not is_e1_decl ->
       (* for __strong e1 = e2 the semantics is*)
diff --git a/infer/src/clang/cTrans.ml b/infer/src/clang/cTrans.ml
index bb358c9f0..6a3254509 100644
--- a/infer/src/clang/cTrans.ml
+++ b/infer/src/clang/cTrans.ml
@@ -84,7 +84,8 @@ struct
       let fname = ModelBuiltins.__set_autorelease_attribute in
       let ret_id = Ident.create_fresh Ident.knormal in
       let stmt_call =
-        Sil.Call ([ret_id], Sil.Const (Const.Cfun fname), [(exp, typ)], sil_loc, Sil.cf_default) in
+        Sil.Call
+          ([ret_id], Sil.Const (Const.Cfun fname), [(exp, typ)], sil_loc, CallFlags.default) in
       [stmt_call]
     else []
 
@@ -878,7 +879,7 @@ struct
                       exps = [(cast_exp, function_type)]; }
                 | None ->
                     let call_flags =
-                      { Sil.cf_default with Sil.cf_is_objc_block = is_call_to_block; } in
+                      { CallFlags.default with CallFlags.cf_is_objc_block = is_call_to_block; } in
                     create_call_instr trans_state function_type sil_fe act_params sil_loc
                       call_flags ~is_objc_method:false in
               let nname = "Call "^(Sil.exp_to_string sil_fe) in
@@ -919,11 +920,11 @@ struct
       (* first expr is method address, rest are params including 'this' parameter *)
       let actual_params = IList.tl (collect_exprs result_trans_subexprs) in
       let call_flags = {
-        Sil.cf_virtual = is_cpp_call_virtual;
-        Sil.cf_interface = false;
-        Sil.cf_noreturn = false;
-        Sil.cf_is_objc_block = false;
-        Sil.cf_targets = [];
+        CallFlags.cf_virtual = is_cpp_call_virtual;
+        CallFlags.cf_interface = false;
+        CallFlags.cf_noreturn = false;
+        CallFlags.cf_is_objc_block = false;
+        CallFlags.cf_targets = [];
       } in
       let res_trans_call = create_call_instr trans_state_pri function_type sil_method actual_params
           sil_loc call_flags ~is_objc_method:false in
@@ -1066,7 +1067,7 @@ struct
         let res_trans_block = { empty_res_trans with
                                 instrs = instr_block_param;
                               } in
-        let call_flags = { Sil.cf_default with Sil.cf_virtual = is_virtual; } in
+        let call_flags = { CallFlags.default with CallFlags.cf_virtual = is_virtual; } in
         let method_sil = Sil.Const (Const.Cfun callee_name) in
         let res_trans_call = create_call_instr trans_state method_type method_sil param_exps
             sil_loc call_flags ~is_objc_method:true in
@@ -1977,7 +1978,7 @@ struct
     let autorelease_pool_vars = CVar_decl.compute_autorelease_pool_vars context stmts in
     let stmt_call =
       Sil.Call([ret_id], (Sil.Const (Const.Cfun fname)),
-               autorelease_pool_vars, sil_loc, Sil.cf_default) in
+               autorelease_pool_vars, sil_loc, CallFlags.default) in
     let node_kind = Cfg.Node.Stmt_node ("Release the autorelease pool") in
     let call_node = create_node node_kind [stmt_call] sil_loc context in
     Cfg.Node.set_succs_exn context.cfg call_node trans_state.succ_nodes [];
@@ -2133,7 +2134,8 @@ struct
     let result_trans_param = exec_with_self_exception instruction trans_state_param param in
     let exp = extract_exp_from_list result_trans_param.exps
         "WARNING: There should be one expression to delete. \n" in
-    let call_instr = Sil.Call ([], Sil.Const (Const.Cfun fname), [exp], sil_loc, Sil.cf_default) in
+    let call_instr =
+      Sil.Call ([], Sil.Const (Const.Cfun fname), [exp], sil_loc, CallFlags.default) in
     let call_res_trans = { empty_res_trans with instrs = [call_instr] } in
     let all_res_trans = if false then
         (* FIXME (t10135167): call destructor on deleted pointer if it's not null *)
@@ -2193,7 +2195,7 @@ struct
     let exp = match res_trans_stmt.exps with | [e] -> e | _ -> assert false in
     let args = [exp; (sizeof_expr, Typ.Tvoid)] in
     let ret_id = Ident.create_fresh Ident.knormal in
-    let call = Sil.Call ([ret_id], builtin, args, sil_loc, Sil.cf_default) in
+    let call = Sil.Call ([ret_id], builtin, args, sil_loc, CallFlags.default) in
     let res_ex = Sil.Var ret_id in
     let res_trans_dynamic_cast = { empty_res_trans with instrs = [call]; } in
     let all_res_trans = [ res_trans_stmt; res_trans_dynamic_cast ] in
@@ -2216,7 +2218,7 @@ struct
     let params = collect_exprs res_trans_subexpr_list  in
     let fun_name = Procname.from_string_c_fun CFrontend_config.infer_skip_gcc_ast_stmt in
     let sil_fun = Sil.Const (Const.Cfun fun_name) in
-    let call_instr = Sil.Call ([], sil_fun, params, sil_loc, Sil.cf_default) in
+    let call_instr = Sil.Call ([], sil_fun, params, sil_loc, CallFlags.default) in
     let res_trans_call = { empty_res_trans with
                            instrs = [call_instr];
                            exps = []; } in
@@ -2249,7 +2251,7 @@ struct
     let ret_exp = Sil.Var ret_id in
     let field_exp = Sil.Lfield (ret_exp, field_name, typ) in
     let args = [type_info_objc; (field_exp, Typ.Tvoid)] @ res_trans_subexpr.exps in
-    let call_instr = Sil.Call ([ret_id], sil_fun, args, sil_loc, Sil.cf_default) in
+    let call_instr = Sil.Call ([ret_id], sil_fun, args, sil_loc, CallFlags.default) in
     let res_trans_call = { empty_res_trans with
                            instrs = [call_instr];
                            exps = [(ret_exp, typ)]; } in
@@ -2272,7 +2274,7 @@ struct
     let sil_fun = Sil.Const (Const.Cfun fun_name) in
     let ret_id = Ident.create_fresh Ident.knormal in
     let ret_exp = Sil.Var ret_id in
-    let call_instr = Sil.Call ([ret_id], sil_fun, params, sil_loc, Sil.cf_default) in
+    let call_instr = Sil.Call ([ret_id], sil_fun, params, sil_loc, CallFlags.default) in
     let res_trans_call = { empty_res_trans with
                            instrs = [call_instr];
                            exps = [(ret_exp, typ)]; } in
diff --git a/infer/src/clang/cTrans_utils.ml b/infer/src/clang/cTrans_utils.ml
index 44111ad38..903f027c2 100644
--- a/infer/src/clang/cTrans_utils.ml
+++ b/infer/src/clang/cTrans_utils.ml
@@ -306,7 +306,8 @@ let create_alloc_instrs context sil_loc function_type fname size_exp_opt procnam
     | None -> [] in
   let args = exp :: procname_arg in
   let ret_id = Ident.create_fresh Ident.knormal in
-  let stmt_call = Sil.Call([ret_id], Sil.Const (Const.Cfun fname), args, sil_loc, Sil.cf_default) in
+  let stmt_call =
+    Sil.Call([ret_id], Sil.Const (Const.Cfun fname), args, sil_loc, CallFlags.default) in
   (function_type, stmt_call, Sil.Var ret_id)
 
 let alloc_trans trans_state loc stmt_info function_type is_cf_non_null_alloc procname_opt =
@@ -328,7 +329,7 @@ let objc_new_trans trans_state loc stmt_info cls_name function_type =
     create_alloc_instrs trans_state.context loc function_type fname None None in
   let init_ret_id = Ident.create_fresh Ident.knormal in
   let is_instance = true in
-  let call_flags = { Sil.cf_default with Sil.cf_virtual = is_instance; } in
+  let call_flags = { CallFlags.default with CallFlags.cf_virtual = is_instance; } in
   let pname = General_utils.mk_procname_from_objc_method cls_name CFrontend_config.init Procname.Instance_objc_method in
   CMethod_trans.create_external_procdesc trans_state.context.CContext.cfg pname is_instance None;
   let args = [(alloc_ret_exp, alloc_ret_type)] in
@@ -371,7 +372,7 @@ let create_cast_instrs context exp cast_from_typ cast_to_typ sil_loc =
   let pname = ModelBuiltins.__objc_cast in
   let args = [(exp, cast_from_typ); (sizeof_exp, Typ.Tint Typ.IULong)] in
   let stmt_call =
-    Sil.Call ([ret_id], Sil.Const (Const.Cfun pname), args, sil_loc, Sil.cf_default) in
+    Sil.Call ([ret_id], Sil.Const (Const.Cfun pname), args, sil_loc, CallFlags.default) in
   (stmt_call, Sil.Var ret_id)
 
 let cast_trans context exps sil_loc callee_pname_opt function_type =
@@ -444,7 +445,7 @@ let cast_operation trans_state cast_kind exps cast_typ sil_loc is_objc_bridged =
 let trans_assertion_failure sil_loc context =
   let assert_fail_builtin = Sil.Const (Const.Cfun ModelBuiltins.__infer_fail) in
   let args = [Sil.Const (Const.Cstr Config.default_failure_name), Typ.Tvoid] in
-  let call_instr = Sil.Call ([], assert_fail_builtin, args, sil_loc, Sil.cf_default) in
+  let call_instr = Sil.Call ([], assert_fail_builtin, args, sil_loc, CallFlags.default) in
   let exit_node = Cfg.Procdesc.get_exit_node (CContext.get_procdesc context)
   and failure_node =
     Nodes.create_node (Cfg.Node.Stmt_node "Assertion failure") [call_instr] sil_loc context in
diff --git a/infer/src/eradicate/typeCheck.ml b/infer/src/eradicate/typeCheck.ml
index b41fc4942..55458ad22 100644
--- a/infer/src/eradicate/typeCheck.ml
+++ b/infer/src/eradicate/typeCheck.ml
@@ -104,8 +104,8 @@ module ComplexExpressions = struct
           pp_to_string (Const.pp pe_text) c
       | Sil.Dderef de ->
           dexp_to_string de
-      | Sil.Dfcall (fun_dexp, args, _, { Sil.cf_virtual = isvirtual })
-      | Sil.Dretcall (fun_dexp, args, _, { Sil.cf_virtual = isvirtual })
+      | Sil.Dfcall (fun_dexp, args, _, { CallFlags.cf_virtual = isvirtual })
+      | Sil.Dretcall (fun_dexp, args, _, { CallFlags.cf_virtual = isvirtual })
         when functions_idempotent () ->
           let pp_arg fmt de = F.fprintf fmt "%s" (dexp_to_string de) in
           let pp_args fmt des = (pp_comma_seq) pp_arg fmt des in
@@ -773,7 +773,7 @@ let typecheck_instr
                   let dexp_get = Sil.Dconst (Const.Cfun pname_get) in
                   let dexp_map = Sil.Dpvar pv_map in
                   let args = [dexp_map; dexp_key] in
-                  let call_flags = { Sil.cf_default with Sil.cf_virtual = true } in
+                  let call_flags = { CallFlags.default with CallFlags.cf_virtual = true } in
                   Some (Sil.Dretcall (dexp_get, args, loc, call_flags))
               | _ -> None in
             begin
@@ -801,7 +801,7 @@ let typecheck_instr
                   EradicateChecks.classify_procedure callee_attributes in
                 L.stdout "  %s unique id: %s@." classification unique_id
               end;
-            if cflags.Sil.cf_virtual && checks.eradicate then
+            if cflags.CallFlags.cf_virtual && checks.eradicate then
               EradicateChecks.check_call_receiver
                 find_canonical_duplicate
                 curr_pname
diff --git a/infer/src/harness/inhabit.ml b/infer/src/harness/inhabit.ml
index f428d3264..deff9514d 100644
--- a/infer/src/harness/inhabit.ml
+++ b/infer/src/harness/inhabit.ml
@@ -50,7 +50,7 @@ let env_add_instr instr env =
   { env with instrs = instr :: env.instrs; pc = incr_pc env.pc }
 
 (** call flags for an allocation or call to a constructor *)
-let cf_alloc = Sil.cf_default
+let cf_alloc = CallFlags.default
 
 let fun_exp_from_name proc_name = Sil.Const (Const.Cfun (proc_name))
 
@@ -158,7 +158,7 @@ and inhabit_constructor constr_name (allocated_obj, obj_type) cfg env =
       inhabit_args non_receiver_formals cfg env in
     let constr_instr =
       let fun_exp = fun_exp_from_name constr_name in
-      Sil.Call ([], fun_exp, (allocated_obj, obj_type) :: args, env.pc, Sil.cf_default) in
+      Sil.Call ([], fun_exp, (allocated_obj, obj_type) :: args, env.pc, CallFlags.default) in
     env_add_instr constr_instr env
   with Not_found -> env
 
@@ -168,7 +168,8 @@ let inhabit_call_with_args procname procdesc args env =
     if is_void then [] else [Ident.create_fresh Ident.knormal] in
   let call_instr =
     let fun_exp = fun_exp_from_name procname in
-    let flags = { Sil.cf_default with Sil.cf_virtual = not (Procname.java_is_static procname); } in
+    let flags =
+      { CallFlags.default with CallFlags.cf_virtual = not (Procname.java_is_static procname); } in
     Sil.Call (retval, fun_exp, args, env.pc, flags) in
   env_add_instr call_instr env
 
diff --git a/infer/src/java/jTrans.ml b/infer/src/java/jTrans.ml
index a16bc4dec..fcf187245 100644
--- a/infer/src/java/jTrans.ml
+++ b/infer/src/java/jTrans.ml
@@ -448,7 +448,7 @@ let rec expression context pc expr =
             let args = [(sil_ex, type_of_ex)] in
             let ret_id = Ident.create_fresh Ident.knormal in
             let call_instr =
-              Sil.Call ([ret_id], builtin_get_array_length, args, loc, Sil.cf_default) in
+              Sil.Call ([ret_id], builtin_get_array_length, args, loc, CallFlags.default) in
             (instrs @ [deref; call_instr], Sil.Var ret_id, type_of_expr)
         | JBir.Conv conv ->
             let cast_ex = Sil.Cast (JTransType.cast_type conv, sil_ex) in
@@ -468,7 +468,7 @@ let rec expression context pc expr =
                | _ -> assert false) in
             let args = [(sil_ex, type_of_ex); (sizeof_expr, Typ.Tvoid)] in
             let ret_id = Ident.create_fresh Ident.knormal in
-            let call = Sil.Call([ret_id], builtin, args, loc, Sil.cf_default) in
+            let call = Sil.Call([ret_id], builtin, args, loc, CallFlags.default) in
             let res_ex = Sil.Var ret_id in
             (instrs @ [call], res_ex, type_of_expr)
       end
@@ -559,8 +559,7 @@ let method_invocation context loc pc var_opt cn ms sil_obj_opt expr_list invoke_
     | I_Virtual -> (true, false)
     | I_Interface -> (true, true)
     | _ -> (false, false) in
-  let call_flags =
-    { Sil.cf_default with Sil.cf_virtual = cf_virtual; Sil.cf_interface = cf_interface; } in
+  let call_flags = { CallFlags.default with cf_virtual; cf_interface; } in
   let init =
     match sil_obj_opt with
     | None -> [], []
@@ -621,7 +620,7 @@ let method_invocation context loc pc var_opt cn ms sil_obj_opt expr_list invoke_
       when Procname.is_constructor callee_procname && JTransType.is_closeable program tenv typ ->
         let set_file_attr =
           let set_builtin = Sil.Const (Const.Cfun ModelBuiltins.__set_file_attribute) in
-          Sil.Call ([], set_builtin, [exp], loc, Sil.cf_default) in
+          Sil.Call ([], set_builtin, [exp], loc, CallFlags.default) in
         (* Exceptions thrown in the constructor should prevent adding the resource attribute *)
         call_instrs @ [set_file_attr]
 
@@ -630,7 +629,7 @@ let method_invocation context loc pc var_opt cn ms sil_obj_opt expr_list invoke_
       when Procname.java_is_close callee_procname && JTransType.is_closeable program tenv typ ->
         let set_mem_attr =
           let set_builtin = Sil.Const (Const.Cfun ModelBuiltins.__set_mem_attribute) in
-          Sil.Call ([], set_builtin, [exp], loc, Sil.cf_default) in
+          Sil.Call ([], set_builtin, [exp], loc, CallFlags.default) in
         (* Exceptions thrown in the close method should not prevent the resource from being *)
         (* considered as closed *)
         [set_mem_attr] @ call_instrs
@@ -763,7 +762,7 @@ let assume_not_null loc sil_expr =
   let builtin_infer_assume = Sil.Const (Const.Cfun ModelBuiltins.__infer_assume) in
   let not_null_expr =
     Sil.BinOp (Binop.Ne, sil_expr, Sil.exp_null) in
-  let assume_call_flag = { Sil.cf_default with Sil.cf_noreturn = true; } in
+  let assume_call_flag = { CallFlags.default with CallFlags.cf_noreturn = true; } in
   let call_args = [(not_null_expr, Typ.Tint Typ.IBool)] in
   Sil.Call ([], builtin_infer_assume, call_args, loc, assume_call_flag)
 
@@ -795,7 +794,7 @@ let rec instruction context pc instr : translation =
   let trans_monitor_enter_exit context expr pc loc builtin node_desc =
     let instrs, sil_expr, sil_type = expression context pc expr in
     let builtin_const = Sil.Const (Const.Cfun builtin) in
-    let instr = Sil.Call ([], builtin_const, [(sil_expr, sil_type)], loc, Sil.cf_default) in
+    let instr = Sil.Call ([], builtin_const, [(sil_expr, sil_type)], loc, CallFlags.default) in
     let typ_no_ptr = match sil_type with
       | Typ.Tptr (typ, _) -> typ
       | _ -> sil_type in
@@ -903,7 +902,7 @@ let rec instruction context pc instr : translation =
         let sizeof_exp = Sil.Sizeof (class_type_np, None, Subtype.exact) in
         let args = [(sizeof_exp, class_type)] in
         let ret_id = Ident.create_fresh Ident.knormal in
-        let new_instr = Sil.Call([ret_id], builtin_new, args, loc, Sil.cf_default) in
+        let new_instr = Sil.Call([ret_id], builtin_new, args, loc, CallFlags.default) in
         let constr_ms = JBasics.make_ms JConfig.constructor_name constr_type_list None in
         let constr_procname, call_instrs =
           let ret_opt = Some (Sil.Var ret_id, class_type) in
@@ -925,7 +924,7 @@ let rec instruction context pc instr : translation =
         let (instrs, array_size) = get_array_length context pc expr_list content_type in
         let call_args = [(array_size, array_type)] in
         let ret_id = Ident.create_fresh Ident.knormal in
-        let call_instr = Sil.Call([ret_id], builtin_new_array, call_args, loc, Sil.cf_default) in
+        let call_instr = Sil.Call([ret_id], builtin_new_array, call_args, loc, CallFlags.default) in
         let set_instr = Sil.Set (Sil.Lvar array_name, array_type, Sil.Var ret_id, loc) in
         let node_kind = Cfg.Node.Stmt_node "method_body" in
         let node = create_node node_kind (instrs @ [call_instr; set_instr]) in
@@ -1017,7 +1016,7 @@ let rec instruction context pc instr : translation =
           let sizeof_exp = Sil.Sizeof (class_type_np, None, Subtype.exact) in
           let args = [(sizeof_exp, class_type)] in
           let ret_id = Ident.create_fresh Ident.knormal in
-          let new_instr = Sil.Call([ret_id], builtin_new, args, loc, Sil.cf_default) in
+          let new_instr = Sil.Call([ret_id], builtin_new, args, loc, CallFlags.default) in
           let constr_ms = JBasics.make_ms JConfig.constructor_name [] None in
           let _, call_instrs =
             let ret_opt = Some (Sil.Var ret_id, class_type) in
@@ -1070,7 +1069,7 @@ let rec instruction context pc instr : translation =
           let sizeof_exp = Sil.Sizeof (class_type_np, None, Subtype.exact) in
           let args = [(sizeof_exp, class_type)] in
           let ret_id = Ident.create_fresh Ident.knormal in
-          let new_instr = Sil.Call([ret_id], builtin_new, args, loc, Sil.cf_default) in
+          let new_instr = Sil.Call([ret_id], builtin_new, args, loc, CallFlags.default) in
           let constr_ms = JBasics.make_ms JConfig.constructor_name [] None in
           let _, call_instrs =
             method_invocation
@@ -1092,7 +1091,7 @@ let rec instruction context pc instr : translation =
           JTransType.sizeof_of_object_type program tenv object_type Subtype.subtypes_instof in
         let check_cast = Sil.Const (Const.Cfun ModelBuiltins.__instanceof) in
         let args = [(sil_expr, sil_type); (sizeof_expr, Typ.Tvoid)] in
-        let call = Sil.Call([ret_id], check_cast, args, loc, Sil.cf_default) in
+        let call = Sil.Call([ret_id], check_cast, args, loc, CallFlags.default) in
         let res_ex = Sil.Var ret_id in
         let is_instance_node =
           let check_is_false = Sil.BinOp (Binop.Ne, res_ex, Sil.exp_zero) in
@@ -1109,7 +1108,7 @@ let rec instruction context pc instr : translation =
           let sizeof_exp = Sil.Sizeof (class_type_np, None, Subtype.exact) in
           let args = [(sizeof_exp, class_type)] in
           let ret_id = Ident.create_fresh Ident.knormal in
-          let new_instr = Sil.Call([ret_id], builtin_new, args, loc, Sil.cf_default) in
+          let new_instr = Sil.Call([ret_id], builtin_new, args, loc, CallFlags.default) in
           let constr_ms = JBasics.make_ms JConfig.constructor_name [] None in
           let _, call_instrs =
             method_invocation context loc pc None cce_cn constr_ms
diff --git a/infer/src/java/jTransExn.ml b/infer/src/java/jTransExn.ml
index 8ddd01a2a..2bb3207be 100644
--- a/infer/src/java/jTransExn.ml
+++ b/infer/src/java/jTransExn.ml
@@ -42,7 +42,8 @@ let translate_exceptions context exit_nodes get_body_nodes handler_table =
     let instr_deactivate_exn = Sil.Set (Sil.Lvar ret_var, ret_type, Sil.Var id_deactivate, loc) in
     let instr_unwrap_ret_val =
       let unwrap_builtin = Sil.Const (Const.Cfun ModelBuiltins.__unwrap_exception) in
-      Sil.Call([id_exn_val], unwrap_builtin, [(Sil.Var id_ret_val, ret_type)], loc, Sil.cf_default) in
+      Sil.Call
+        ([id_exn_val], unwrap_builtin, [(Sil.Var id_ret_val, ret_type)], loc, CallFlags.default) in
     create_node
       loc
       Cfg.Node.exn_handler_kind
@@ -70,7 +71,7 @@ let translate_exceptions context exit_nodes get_body_nodes handler_table =
           let args = [
             (Sil.Var id_exn_val, Typ.Tptr(exn_type, Typ.Pk_pointer));
             (Sil.Sizeof (exn_type, None, Subtype.exact), Typ.Tvoid)] in
-          Sil.Call ([id_instanceof], instanceof_builtin, args, loc, Sil.cf_default) in
+          Sil.Call ([id_instanceof], instanceof_builtin, args, loc, CallFlags.default) in
         let if_kind = Sil.Ik_switch in
         let instr_prune_true = Sil.Prune (Sil.Var id_instanceof, loc, true, if_kind) in
         let instr_prune_false =
diff --git a/infer/src/java/jTransStaticField.ml b/infer/src/java/jTransStaticField.ml
index f12f81178..40ecbf008 100644
--- a/infer/src/java/jTransStaticField.ml
+++ b/infer/src/java/jTransStaticField.ml
@@ -187,7 +187,8 @@ let translate_instr_static_field context callee_procdesc fs field_type loc =
   let callee_procname = Cfg.Procdesc.get_proc_name callee_procdesc in
   let callee_fun = Sil.Const (Const.Cfun callee_procname) in
   let field_arg = Sil.Const (Const.Cstr (JBasics.fs_name fs)) in
-  let call_instr = Sil.Call([ret_id], callee_fun, [field_arg, field_type], loc, Sil.cf_default) in
+  let call_instr =
+    Sil.Call ([ret_id], callee_fun, [field_arg, field_type], loc, CallFlags.default) in
   Cg.add_edge cg caller_procname callee_procname;
   ([call_instr], Sil.Var ret_id)
 
diff --git a/infer/src/llvm/lTrans.ml b/infer/src/llvm/lTrans.ml
index 0e8c3eebe..8f3c99d02 100644
--- a/infer/src/llvm/lTrans.ml
+++ b/infer/src/llvm/lTrans.ml
@@ -99,7 +99,7 @@ let rec trans_annotated_instructions
                 [ident_of_variable ret_var],
                 Sil.Const (Const.Cfun (procname_of_function_variable func_var)),
                 IList.map (fun (tp, arg) -> (trans_operand arg, trans_typ tp)) typed_args,
-                location, Sil.cf_default) in
+                location, CallFlags.default) in
             (new_sil_instr :: sil_instrs, locals)
         | _ -> raise (Unimplemented "Need to translate instruction to SIL.")
       end
diff --git a/infer/src/unit/analyzerTester.ml b/infer/src/unit/analyzerTester.ml
index 9143862b0..26a97c529 100644
--- a/infer/src/unit/analyzerTester.ml
+++ b/infer/src/unit/analyzerTester.ml
@@ -92,7 +92,7 @@ module StructuredSil = struct
 
   let make_call ?(procname=dummy_procname) ret_ids args =
     let call_exp = Sil.Const (Const.Cfun procname) in
-    Cmd (Sil.Call (ret_ids, call_exp, args, dummy_loc, Sil.cf_default))
+    Cmd (Sil.Call (ret_ids, call_exp, args, dummy_loc, CallFlags.default))
 
   let id_assign_id ?(rhs_typ=dummy_typ) lhs rhs =
     let lhs_id = ident_of_str lhs in