Move maxConstraint computation to RunInfo to avoid references to stale symbols.

1 files changed, 10 insertions, 9 deletions

diff --git a/src/dotty/tools/dotc/core/Constraint.scala b/src/dotty/tools/dotc/core/Constraint.scala
index 1df3c6ac5..010601450 100644
--- a/src/dotty/tools/dotc/core/Constraint.scala
+++ b/src/dotty/tools/dotc/core/Constraint.scala
@@ -72,13 +72,9 @@ class Constraint(val myMap: SimpleMap[PolyType, Array[Type]]) extends AnyVal wit
    *  the entries corresponding to `pt` with `entries`.
    */
   private def updateEntries(pt: PolyType, entries: Array[Type])(implicit ctx: Context) : Constraint = {
-    import Constraint._
     val res = new Constraint(myMap.updated(pt, entries))
     if (Config.checkConstraintsNonCyclic) checkNonCyclic(pt, entries)
-    if (res.myMap.size > maxSize) {
-      maxSize = res.myMap.size
-      maxConstraint = res
-    }
+    ctx.runInfo.recordConstraintSize(res)
     res
   }
 
@@ -294,9 +290,14 @@ class Constraint(val myMap: SimpleMap[PolyType, Array[Type]]) extends AnyVal wit
   }
 }
 
-object Constraint {
-  var maxSize = 0
-  var maxConstraint: Constraint = _
-  def printMax()(implicit ctx: Context) =
+trait ConstraintRunInfo { self: RunInfo =>
+  private var maxSize = 0
+  private var maxConstraint: Constraint = _
+  def recordConstraintSize(c: Constraint) =
+    if (c.myMap.size > maxSize) {
+      maxSize = c.myMap.size
+      maxConstraint = c
+    }
+  def printMaxConstraint()(implicit ctx: Context) =
     if (maxSize > 0) println(s"max constraint = ${maxConstraint.show}")
 }