bring back Linol_eio.spawn for logging uncaught exceptions

example/template-eio/main.ml

@@ -45,7 +45,7 @@ class lsp_server ~(sw: Eio.Switch.t) =
     val buffers : (Lsp.Types.DocumentUri.t, state_after_processing) Hashtbl.t =
       Hashtbl.create 32
 
-    method spawn_query_handler f = Eio.Fiber.fork ~sw f
+    method spawn_query_handler f = Linol_eio.spawn ~sw f
 
     (* We define here a helper method that will:
        - process a document

src/eio/linol_eio.ml

@@ -51,6 +51,16 @@ module IO_eio :
   let read_line in_ch = Eio.Buf_read.line in_ch
 end
 
+(** Spawn function. *)
+let spawn ~sw f =
+  Eio.Fiber.fork ~sw (fun () ->
+   try
+     f ()
+   with exn ->
+     Printf.eprintf "uncaught exception in `spawn`:\n%s\n%!"
+       (Printexc.to_string exn);
+     raise exn)
+
 include Lsp.Types
 include IO_eio