Don't eagerly evaluate assertion failure strings

Users should assume it's OK to make them expensive to evaluate.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/main/scala/Chisel/CoreUtil.scala b/src/main/scala/Chisel/CoreUtil.scala
index db3cf678..bad7799a 100644
--- a/src/main/scala/Chisel/CoreUtil.scala
+++ b/src/main/scala/Chisel/CoreUtil.scala
@@ -59,7 +59,7 @@ object assert {
 
   /** An elaboration-time assertion, otherwise the same as the above run-time
     * assertion. */
-  def apply(cond: Boolean, message: String) {
+  def apply(cond: Boolean, message: => String) {
     Predef.assert(cond, message)
   }