Use input element to decide if Vec of values has direction (#570)

Using the sample_element of the created wire is incorrect because Wires have no
direction so the Wire constructed for a Vec of Module IO was constructed
incorrectly. Fixes #569 and resolves #522.

1 files changed, 3 insertions, 1 deletions

diff --git a/chiselFrontend/src/main/scala/chisel3/core/Aggregate.scala b/chiselFrontend/src/main/scala/chisel3/core/Aggregate.scala
index a561e7d5..be874042 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/Aggregate.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/Aggregate.scala
@@ -73,7 +73,9 @@ object Vec {
 
     def doConnect(sink: T, source: T) = {
       // TODO: this looks bad, and should feel bad. Replace with a better abstraction.
-      val hasDirectioned = vec.sample_element match {
+      // NOTE: Must use elts.head instead of vec.sample_element because vec.sample_element has
+      //       WireBinding which does not have a direction
+      val hasDirectioned = elts.head match {
         case t: Aggregate => t.flatten.exists(_.dir != Direction.Unspecified)
         case t: Element => t.dir != Direction.Unspecified
       }