Compiler: fix 827 (#828)

Author: hhugo

compiler/lib/eval.ml

@@ -360,7 +360,7 @@ let drop_exception_handler blocks =
   Addr.Map.fold
     (fun pc _ blocks ->
       match Addr.Map.find pc blocks with
-      | { branch = Pushtrap (((addr, _) as cont1), _x, _cont2, _)
+      | { branch = Pushtrap (((addr, _) as cont1), _x, _cont2, addrset)
         ; handler = parent_hander
         ; _ } as b -> (
         try
@@ -374,8 +374,8 @@ let drop_exception_handler blocks =
                 assert (Poly.(b.handler <> parent_hander));
                 let branch =
                   match b.branch with
-                  | Poptrap (cont, pushtrap) ->
-                      assert (pc = pushtrap);
+                  | Poptrap (((addr, _) as cont), _) ->
+                      assert (Addr.Set.mem addr addrset);
                       Branch cont
                   | x -> x
                 in

compiler/tests/eliminate_exception_handler.ml

@@ -0,0 +1,61 @@
+(* Js_of_ocaml compiler
+ * http://www.ocsigen.org/js_of_ocaml/
+ * Copyright (C) 2019 Hugo Heuzard
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, with linking exception;
+ * either version 2.1 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *)
+open Util
+
+(* https://github.com/ocsigen/js_of_ocaml/issues/827 *)
+
+let%expect_test _ =
+  let compile s =
+    s
+    |> Filetype.ocaml_text_of_string
+    |> Filetype.write_ocaml
+    |> compile_ocaml_to_cmo
+    |> compile_cmo_to_javascript ~pretty:true
+    |> fst
+    |> parse_js
+  in
+  let program =
+    compile
+      {|
+[@@@ocaml.warning "-26-27"]
+let some_name () =
+try raise Not_found with
+| f ->
+      (try fun g -> 0 with h -> fun h -> raise Not_found)
+        (let o =
+           ( try
+               fun a ->
+                 try try fun c -> 0 with q -> raise (Not_found) with
+                 | f ->
+                     raise Not_found
+             with
+           | h ->
+             (raise Not_found) )
+             ()
+         in
+         try
+           let m = try [] with j -> [] in
+           true
+         with
+         | s ->
+             true)
+                   |}
+  in
+  print_fun_decl program "some_name";
+  [%expect {| function some_name(param){try {throw Stdlib[8]}catch(_a_){return 0}} |}]