Reduce rocket-chip elaboration errors.

1 files changed, 2 insertions, 0 deletions

diff --git a/chiselFrontend/src/main/scala/chisel3/core/MonoConnect.scala b/chiselFrontend/src/main/scala/chisel3/core/MonoConnect.scala
index bf8e7e28..e0c95e80 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/MonoConnect.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/MonoConnect.scala
@@ -118,6 +118,7 @@ object MonoConnect {
         //    CURRENT MOD   CURRENT MOD
         case (Some(Output), _) => issueConnect(sink, source)
         case (None,         _) => issueConnect(sink, source)
+        case (_,         None) if (compileOptions.internalConnectionToInputOk) => issueConnect(sink, source)
         case (Some(Input),  _) => throw UnwritableSinkException
       }
     }
@@ -134,6 +135,7 @@ object MonoConnect {
         case (Some(Output), Some(Output)) => issueConnect(sink, source)
         case (Some(Output), Some(Input))  => issueConnect(sink, source)
         case (_,            None) => throw UnreadableSourceException
+        case (Some(Input),  Some(Output)) if (compileOptions.tryConnectionsSwapped) => issueConnect(source, sink)
         case (Some(Input),  _)    => throw UnwritableSinkException
       }
     }