diff --git a/infer/src/backend/errdesc.ml b/infer/src/backend/errdesc.ml
index 1a6c0c6ab..494677e5c 100644
--- a/infer/src/backend/errdesc.ml
+++ b/infer/src/backend/errdesc.ml
@@ -1148,16 +1148,7 @@ let explain_null_test_after_dereference exp node line loc =
       Localise.desc_null_test_after_dereference expr_str line loc
   | None -> Localise.no_desc
 
-let _warning loc fmt fmt_string =
-  if Config.developer_mode then
-    begin
-      F.fprintf
-        fmt "%s:%d: Warning: " (DB.source_file_to_string !DB.current_source) loc.Location.line;
-      F.fprintf fmt fmt_string
-    end
-  else
-    F.ifprintf fmt fmt_string
-
 (** Print a warning to the err stream at the given location (note: only prints in developer mode) *)
 let warning_err loc fmt_string =
-  _warning loc (Logging.get_err_formatter ()) fmt_string
+  L.err ("%s:%d: Warning: " ^^ fmt_string)
+    (DB.source_file_to_string !DB.current_source) loc.Location.line
diff --git a/infer/src/backend/inferanalyze.ml b/infer/src/backend/inferanalyze.ml
index 7170aaefe..e5877d43c 100644
--- a/infer/src/backend/inferanalyze.ml
+++ b/infer/src/backend/inferanalyze.ml
@@ -64,48 +64,6 @@ let analyze_cluster cluster_num (cluster : Cluster.t) =
     (cluster_num + 1) num_procs;
   analyze_exe_env exe_env
 
-let open_output_file f fname =
-  try
-    let cout = open_out fname in
-    let fmt = Format.formatter_of_out_channel cout in
-    f fmt;
-    Some (fmt, cout)
-  with Sys_error _ ->
-    Format.fprintf Format.std_formatter "Error: cannot open output file %s@." fname;
-    exit(-1)
-
-let close_output_file = function
-  | None -> ()
-  | Some (_, cout) -> close_out cout
-
-let setup_logging () =
-  if Config.developer_mode then
-    let log_dir_name = "log" in
-    let analyzer_out_name = "analyzer_out" in
-    let analyzer_err_name = "analyzer_err" in
-    let log_dir =
-      DB.filename_to_string
-        (DB.Results_dir.path_to_filename DB.Results_dir.Abs_root [log_dir_name]) in
-    DB.create_dir log_dir;
-    let analyzer_out_file =
-      if Config.out_file_cmdline = "" then Filename.concat log_dir analyzer_out_name
-      else Config.out_file_cmdline in
-    let analyzer_err_file =
-      if Config.err_file_cmdline = "" then Filename.concat log_dir analyzer_err_name
-      else Config.err_file_cmdline in
-    let analyzer_out_of = open_output_file Logging.set_out_formatter analyzer_out_file in
-    let analyzer_err_of = open_output_file Logging.set_err_formatter analyzer_err_file in
-    analyzer_out_of, analyzer_err_of
-  else None, None
-
-let teardown_logging analyzer_out_of analyzer_err_of =
-  if Config.developer_mode then
-    begin
-      L.flush_streams ();
-      close_output_file analyzer_out_of;
-      close_output_file analyzer_err_of;
-    end
-
 let output_json_makefile_stats clusters =
   let clusters_to_analyze =
     IList.filter ClusterMakefile.cluster_should_be_analyzed clusters in
@@ -167,15 +125,9 @@ let () =
   if Config.allow_specs_cleanup = true && Config.cluster_cmdline = None then
     DB.Results_dir.clean_specs_dir ();
 
-  let analyzer_out_of, analyzer_err_of = setup_logging () in
-
-  let finish_logging () =
-    teardown_logging analyzer_out_of analyzer_err_of in
-
   match Config.cluster_cmdline with
   | Some fname ->
-      process_cluster_cmdline fname;
-      finish_logging ()
+      process_cluster_cmdline fname
   | None ->
       if Config.merge then MergeCapture.merge_captured_targets ();
       let clusters = DB.find_source_dirs () in
@@ -192,5 +144,4 @@ let () =
             clusters;
           L.stdout "Analysis finished in %as@." pp_elapsed_time ()
         end;
-      output_json_makefile_stats clusters;
-      finish_logging ()
+      output_json_makefile_stats clusters
diff --git a/infer/src/backend/logging.ml b/infer/src/backend/logging.ml
index 8e2442863..9a2eb7cbe 100644
--- a/infer/src/backend/logging.ml
+++ b/infer/src/backend/logging.ml
@@ -14,7 +14,6 @@ open! Utils
 
 module F = Format
 
-(* =============== START of module MyErr =============== *)
 (** type of printable elements *)
 type print_type =
   | PTatom
@@ -64,35 +63,57 @@ let delayed_actions = ref []
 (** hook for the current printer of delayed print actions *)
 let printer_hook = ref (Obj.magic ())
 
-(** Current formatter for the out stream *)
-let current_out_formatter = ref F.std_formatter
-
-(** Current formatter for the err stream *)
-let current_err_formatter = ref F.err_formatter
-
-(** Get the current err formatter *)
-let get_err_formatter () = !current_err_formatter
-
-(** Set the current out formatter *)
-let set_out_formatter fmt =
-  current_out_formatter := fmt
-
-(** Set the current err formatter *)
-let set_err_formatter fmt =
-  current_err_formatter := fmt
-
-(** Flush the current streams *)
-let flush_streams () =
+let out_formatter, err_formatter =
+  (** Create a directory if it does not exist already. *)
+  (* This is the same as DB.create_dir, except for logging to stderr *)
+  let create_dir dir =
+    try
+      if (Unix.stat dir).Unix.st_kind != Unix.S_DIR then
+        failwithf "@.ERROR: file %s exists and is not a directory@." dir
+    with Unix.Unix_error _ ->
+    try Unix.mkdir dir 0o700
+    with Unix.Unix_error _ ->
+      let created_concurrently = (* check if another process created it meanwhile *)
+        (Unix.stat dir).Unix.st_kind = Unix.S_DIR in
+      if not created_concurrently then
+        failwithf "@.ERROR: cannot create directory %s@." dir
+  in
+  let open_output_file fname =
+    try
+      let cout = open_out fname in
+      let fmt = F.formatter_of_out_channel cout in
+      (fmt, cout)
+    with Sys_error _ ->
+      failwithf "@.ERROR: cannot open output file %s@." fname
+  in
   if Config.developer_mode then
-    begin
-      F.fprintf !current_out_formatter "@?";
-      F.fprintf !current_err_formatter "@?"
-    end
+    let log_dir_name = "log" in
+    let analyzer_out_name = "analyzer_out" in
+    let analyzer_err_name = "analyzer_err" in
+    let log_dir = Filename.concat Config.results_dir log_dir_name in
+    create_dir log_dir;
+    let analyzer_out_file =
+      if Config.out_file_cmdline = "" then Filename.concat log_dir analyzer_out_name
+      else Config.out_file_cmdline in
+    let analyzer_err_file =
+      if Config.err_file_cmdline = "" then Filename.concat log_dir analyzer_err_name
+      else Config.err_file_cmdline in
+    let out_fmt, out_chan = open_output_file analyzer_out_file in
+    let err_fmt, err_chan = open_output_file analyzer_err_file in
+    Pervasives.at_exit (fun () ->
+        F.pp_print_flush out_fmt () ;
+        F.pp_print_flush err_fmt () ;
+        close_out out_chan ;
+        close_out err_chan
+      );
+    (out_fmt, err_fmt)
+  else
+    (F.std_formatter, F.err_formatter)
 
 (** extend the current print log *)
 let add_print_action pact =
   if Config.write_html then delayed_actions := pact :: !delayed_actions
-  else if not Config.test then !printer_hook !current_out_formatter pact
+  else if not Config.test then !printer_hook out_formatter pact
 
 (** reset the delayed print actions *)
 let reset_delayed_prints () =
@@ -117,11 +138,11 @@ let do_print_in_developer_mode fmt fmt_string =
 
 (** print to the current out stream (note: only prints in developer mode) *)
 let out fmt_string =
-  do_print_in_developer_mode !current_out_formatter fmt_string
+  do_print_in_developer_mode out_formatter fmt_string
 
 (** print to the current err stream (note: only prints in developer mode) *)
 let err fmt_string =
-  do_print_in_developer_mode !current_err_formatter fmt_string
+  do_print_in_developer_mode err_formatter fmt_string
 
 (** print immediately to standard error *)
 let stderr fmt_string =
diff --git a/infer/src/backend/logging.mli b/infer/src/backend/logging.mli
index 684d41d55..90a2432b6 100644
--- a/infer/src/backend/logging.mli
+++ b/infer/src/backend/logging.mli
@@ -83,18 +83,6 @@ val stderr : ('a, Format.formatter, unit) format -> 'a
 (** print immediately to standard output *)
 val stdout : ('a, Format.formatter, unit) format -> 'a
 
-(** Get the current err formatter *)
-val get_err_formatter : unit -> Format.formatter
-
-(** Set the current out formatter *)
-val set_out_formatter : Format.formatter -> unit
-
-(** Set the current err formatter *)
-val set_err_formatter : Format.formatter -> unit
-
-(** Flush the current streams *)
-val flush_streams : unit -> unit
-
 (** Type of location in ml source: __POS__ *)
 type ml_loc = string * int * int * int
 
diff --git a/infer/src/backend/utils.ml b/infer/src/backend/utils.ml
index 701efe77d..a3a9f4579 100644
--- a/infer/src/backend/utils.ml
+++ b/infer/src/backend/utils.ml
@@ -599,3 +599,11 @@ let with_file file ~f =
 
 let write_json_to_file destfile json =
   with_file destfile ~f:(fun oc -> Yojson.Basic.pretty_to_channel oc json)
+
+let failwithf fmt =
+  Format.kfprintf (fun _ -> failwith (Format.flush_str_formatter ()))
+    Format.str_formatter fmt
+
+let invalid_argf fmt =
+  Format.kfprintf (fun _ -> invalid_arg (Format.flush_str_formatter ()))
+    Format.str_formatter fmt
diff --git a/infer/src/backend/utils.mli b/infer/src/backend/utils.mli
index 259e2c592..602d2ec9b 100644
--- a/infer/src/backend/utils.mli
+++ b/infer/src/backend/utils.mli
@@ -269,3 +269,7 @@ val analyzer_of_string: string -> analyzer
 val read_optional_json_file : string -> (Yojson.Basic.json, string) result
 
 val write_json_to_file : string -> Yojson.Basic.json -> unit
+
+val failwithf : ('a, Format.formatter, unit, 'b) format4 -> 'a
+
+val invalid_argf : ('a, Format.formatter, unit, 'b) format4 -> 'a
diff --git a/infer/src/scripts/checkCopyright.ml b/infer/src/scripts/checkCopyright.ml
index 2a1cce033..e1d49c739 100644
--- a/infer/src/scripts/checkCopyright.ml
+++ b/infer/src/scripts/checkCopyright.ml
@@ -217,7 +217,6 @@ let output_diff fname lines_arr cstart n cend len mono fb_year com_style prefix
   done;
   L.stdout "-----@.";
   L.stdout "@[<v>%a@]" (pp_copyright mono fb_year com_style) prefix;
-  L.flush_streams ();
   if !update_files then
     update_file fname mono fb_year com_style prefix cstart cend lines_arr