From 5c16d2c41aea1b239cc48777c7fefcc5f919d6ed Mon Sep 17 00:00:00 2001
From: odersky <odersky@gmail.com>
Date: Fri, 2 Sep 2022 12:05:41 +0200
Subject: [PATCH] Handle stackoverflows when trying to print the maximal
 constraint

---
 compiler/src/dotty/tools/dotc/core/ConstraintRunInfo.scala | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/core/ConstraintRunInfo.scala b/compiler/src/dotty/tools/dotc/core/ConstraintRunInfo.scala
index 61d1ee0de58a..d2b1246a8149 100644
--- a/compiler/src/dotty/tools/dotc/core/ConstraintRunInfo.scala
+++ b/compiler/src/dotty/tools/dotc/core/ConstraintRunInfo.scala
@@ -13,9 +13,11 @@ trait ConstraintRunInfo { self: Run =>
       maxConstraint = c
     }
   def printMaxConstraint()(using Context): Unit =
-    val printer = if (ctx.settings.YdetailedStats.value) default else typr
     if maxSize > 0 then
-      printer.println(s"max constraint = ${maxConstraint.nn.show}\nsize = $maxSize")
+      val printer = if ctx.settings.YdetailedStats.value then default else typr
+      printer.println(s"max constraint size: $maxSize")
+      try printer.println(s"max constraint = ${maxConstraint.nn.show}")
+      catch case ex: StackOverflowError => printer.println("max constraint cannot be printed due to stack overflow")
 
   protected def reset(): Unit = maxConstraint = null
 }