Clarify types and print stack-trace on exception in parser

Author: JonasAlaif

src/main/scala/viper/silver/parser/FastParser.scala

@@ -38,7 +38,7 @@ object FastParser {
     */
   def FP[T](t: => P[T])(implicit ctx: P[_]): P[((FilePosition, FilePosition), T)] = {
     val startPos = LineCol(ctx.index)
-    val res = t
+    val res: P[T] = t
     val finishPos = LineCol(ctx.index)
     res.map({ parsed => ((FilePosition(_file, startPos._1, startPos._2), FilePosition(_file, finishPos._1, finishPos._2)), parsed) })
   }

src/main/scala/viper/silver/reporter/Reporter.scala

@@ -112,8 +112,10 @@ case class StdIOReporter(name: String = "stdout_reporter", timeInfo: Boolean = t
 
       case ExceptionReport(e) =>
         /** Theoretically, we may encounter an exceptional message that has
-          * not yet been reported via AbortedExceptionally. */
+          * not yet been reported via AbortedExceptionally. This can happen
+          * if we encounter exeptions in e.g. the parser. */
         println( s"Verification aborted exceptionally: ${e.toString}" )
+        e.printStackTrace(System.out);
         Option(e.getCause) match {
           case Some(cause) => println( s"  Cause: ${cause.toString}" )
           case None =>