[wibble] refactor error output

Summary: Also makes the error message for clang commands a bit nicer to the eye.

Reviewed By: mbouaziz

Differential Revision: D5191664

fbshipit-source-id: 801ec72

infer/src/base/Config.ml

@@ -1706,9 +1706,9 @@ let post_parsing_initialization command_opt =
     Caml.Printexc.set_uncaught_exception_handler
       (fun exn _ ->
          let exn_msg = match exn with
-           | Failure msg -> "ERROR: " ^ msg
-           | _ -> "ERROR: " ^ Caml.Printexc.to_string exn in
-         Format.eprintf "%s@?" exn_msg
+           | Failure msg -> msg
+           | _ -> Caml.Printexc.to_string exn in
+         Format.eprintf "ERROR: %s@." exn_msg
       );
 
   F.set_margin !margin ;

infer/src/clang/ClangWrapper.re

@@ -128,7 +128,7 @@ let exec_action_item =
     /* An error in the output of `clang -### ...`. Outputs the error and fail. This is because
        `clang -###` pretty much never fails, but warns of failures on stderr instead. */
     failwithf
-      "@\n*** ERROR: Failed to execute compilation command. Output:@\n%s@\n*** Infer needs a working compilation command to run.@."
+      "Failed to execute compilation command. Output:@\n%s@\n*** Infer needs a working compilation command to run."
       error
   | ClangWarning warning => L.external_warning "%s@\n" warning
   | Command clang_cmd => Capture.capture clang_cmd;