Make asTypeOf work for bundles with zero-width fields. (#1079)

Closes #1075.

1 files changed, 22 insertions, 0 deletions

diff --git a/src/test/scala/chiselTests/AsTypeOfTester.scala b/src/test/scala/chiselTests/AsTypeOfTester.scala
index c78ddb17..563e2b11 100644
--- a/src/test/scala/chiselTests/AsTypeOfTester.scala
+++ b/src/test/scala/chiselTests/AsTypeOfTester.scala
@@ -27,6 +27,24 @@ class AsTypeOfBundleTester extends BasicTester {
   stop()
 }
 
+class AsTypeOfBundleZeroWidthTester extends BasicTester {
+  class ZeroWidthBundle extends Bundle {
+    val a = UInt(0.W)
+    val b = UInt(1.W)
+    val c = UInt(0.W)
+  }
+
+  val bun = new ZeroWidthBundle
+
+  val bunAsTypeOf = 1.U.asTypeOf(bun)
+
+  assert(bunAsTypeOf.a === 0.U)
+  assert(bunAsTypeOf.b === 1.U)
+  assert(bunAsTypeOf.c === 0.U)
+
+  stop()
+}
+
 class AsTypeOfVecTester extends BasicTester {
   val vec = ((15 << 12) + (0 << 8) + (1 << 4) + (2 << 0)).U.asTypeOf(Vec(4, SInt(4.W)))
 
@@ -103,6 +121,10 @@ class AsTypeOfSpec extends ChiselFlatSpec {
     assertTesterPasses{ new AsTypeOfBundleTester }
   }
 
+  it should "work with Bundles that have fields of zero width" in {
+    assertTesterPasses{ new AsTypeOfBundleZeroWidthTester }
+  }
+
   it should "work with Vecs containing Bits Types" in {
     assertTesterPasses{ new AsTypeOfVecTester }
   }