Deprecate accessing the name of non-hardware Data (#2550) (#2552)

This includes (and is tested) for both the old .*Name APIs and
.toTarget

(cherry picked from commit 6e0d8d6b12e9d8f94c2cc43b92b2366ec70dfd50)

Co-authored-by: Jack Koenig <koenig@sifive.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/core/src/main/scala/chisel3/internal/Builder.scala b/core/src/main/scala/chisel3/internal/Builder.scala
index 69455455..97c3bc49 100644
--- a/core/src/main/scala/chisel3/internal/Builder.scala
+++ b/core/src/main/scala/chisel3/internal/Builder.scala
@@ -240,7 +240,18 @@ private[chisel3] trait HasId extends InstanceId {
 
   private def refName(c: Component): String = _ref match {
     case Some(arg) => arg.fullName(c)
-    case None      => _computeName(None, None).get
+    case None      =>
+      // This is super hacky but this is just for a short term deprecation
+      // These accesses occur after Chisel elaboration so we cannot use the normal
+      // Builder.deprecated mechanism, we have to create our own one off ErrorLog and print the
+      // warning right away.
+      val errors = new ErrorLog
+      val logger = new _root_.logger.Logger(this.getClass.getName)
+      val msg = "Accessing the .instanceName or .toTarget of non-hardware Data is deprecated. " +
+        "This will become an error in Chisel 3.6."
+      errors.deprecated(msg, None)
+      errors.checkpoint(logger)
+      _computeName(None, None).get
   }
 
   // Helper for reifying views if they map to a single Target