2 files changed, 9 insertions, 4 deletions
diff --git a/src/main/scala/firrtl/annotations/JsonProtocol.scala b/src/main/scala/firrtl/annotations/JsonProtocol.scala
index 312b826a..941bf003 100644
--- a/src/main/scala/firrtl/annotations/JsonProtocol.scala
+++ b/src/main/scala/firrtl/annotations/JsonProtocol.scala
@@ -122,6 +122,10 @@ object JsonProtocol {
     { case JString(s) => Parser.parseInfo(s) },
     { case info: Info => JString(info.serialize) }
   ))
+  class GroundTypeSerializer extends CustomSerializer[GroundType](format => (
+    { case JString(s) => Parser.parseType(s).asInstanceOf[GroundType] },
+    { case tpe: GroundType => JString(tpe.serialize) }
+  ))
 
   /** Construct Json formatter for annotations */
   def jsonFormat(tags: Seq[Class[_]]) = {
@@ -133,7 +137,7 @@ object JsonProtocol {
       new LoadMemoryFileTypeSerializer + new IsModuleSerializer + new IsMemberSerializer +
       new CompleteTargetSerializer + new TypeSerializer + new ExpressionSerializer +
       new StatementSerializer + new PortSerializer + new DefModuleSerializer +
-      new CircuitSerializer + new InfoSerializer
+      new CircuitSerializer + new InfoSerializer + new GroundTypeSerializer
   }
 
   /** Serialize annotations to a String for emission */
diff --git a/src/test/scala/firrtlTests/annotationTests/JsonProtocolSpec.scala b/src/test/scala/firrtlTests/annotationTests/JsonProtocolSpec.scala
index 2dce89db..507c5291 100644
--- a/src/test/scala/firrtlTests/annotationTests/JsonProtocolSpec.scala
+++ b/src/test/scala/firrtlTests/annotationTests/JsonProtocolSpec.scala
@@ -14,7 +14,8 @@ case class AnAnnotation(
     port: Port,
     statement: Statement,
     expr: Expression,
-    tpe: Type
+    tpe: Type,
+    groundType: GroundType
 ) extends NoTargetAnnotation
 
 class JsonProtocolSpec extends FlatSpec with Matchers {
@@ -33,10 +34,10 @@ class JsonProtocolSpec extends FlatSpec with Matchers {
     val stmt = mod.asInstanceOf[Module].body
     val expr = stmt.asInstanceOf[Block].stmts.head.asInstanceOf[Connect].expr
     val tpe = port.tpe
-    val inputAnnos = Seq(AnAnnotation(cir.info, cir, mod, port, stmt, expr, tpe))
+    val groundType = port.tpe.asInstanceOf[GroundType]
+    val inputAnnos = Seq(AnAnnotation(cir.info, cir, mod, port, stmt, expr, tpe, groundType))
     val annosString = JsonProtocol.serialize(inputAnnos)
     val outputAnnos = JsonProtocol.deserialize(annosString)
     inputAnnos should be (outputAnnos)
   }
-
 }