From 41e98161c5a5d58f50fdc86d3725bd10fa6d08ee Mon Sep 17 00:00:00 2001
From: Fengyun Liu <fengyun.liu.cs@gmail.com>
Date: Thu, 29 Aug 2024 23:35:21 +0200
Subject: [PATCH] Fix bug in capture analysis of closures

---
 .../tools/dotc/transform/init/Objects.scala   |  9 ++++---
 tests/init-global/pos/footprint2.scala        | 26 +++++++++++++++++++
 2 files changed, 32 insertions(+), 3 deletions(-)
 create mode 100644 tests/init-global/pos/footprint2.scala

diff --git a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
index fe5fce2e1c11..a9cbf01c1523 100644
--- a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
+++ b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
@@ -255,6 +255,7 @@ class Objects(using Context @constructorOnly):
             case vdef: ValDef =>
               val sym = vdef.symbol
               if sym.isLocal then defs += sym
+              traverseChildren(vdef.rhs)
 
             case _ =>
               traverseChildren(tree)
@@ -680,8 +681,10 @@ class Objects(using Context @constructorOnly):
         val changeSetBefore = Heap.getChangeSet()
         // Only perform footprint optimization for method context
         val footprint =
-          if ctx == EvalContext.Method then Heap.footprint(Heap.getHeapData(), thisV, env, State.currentObjectRef)
-          else heapBefore
+          if ctx == EvalContext.Method then
+            Heap.footprint(Heap.getHeapData(), thisV, env, State.currentObjectRef)
+          else
+            heapBefore
         val config = Config(thisV, env, footprint)
 
         Heap.update(footprint, changeSet = Set.empty)
@@ -1267,7 +1270,7 @@ class Objects(using Context @constructorOnly):
    * @param klass       The enclosing class where the expression is located.
    * @param ctx         The context where `eval` is called.
    */
-  def eval(expr: Tree, thisV: ThisValue, klass: ClassSymbol, ctx: EvalContext = EvalContext.Other): Contextual[Value] = log("evaluating " + expr.show + ", this = " + thisV.show + ", regions = " + Regions.show + " in " + klass.show, printer, (_: Value).show) {
+  def eval(expr: Tree, thisV: ThisValue, klass: ClassSymbol, ctx: EvalContext = EvalContext.Other): Contextual[Value] = log("evaluating " + expr.show + ", this = " + thisV.show + ", heap size = " + Heap.getHeapData().size + " in " + klass.show, printer, (_: Value).show) {
     cache.cachedEval(thisV, expr, ctx) { expr => cases(expr, thisV, klass) }
   }
 
diff --git a/tests/init-global/pos/footprint2.scala b/tests/init-global/pos/footprint2.scala
new file mode 100644
index 000000000000..dc88896b7929
--- /dev/null
+++ b/tests/init-global/pos/footprint2.scala
@@ -0,0 +1,26 @@
+class BreakControl extends Throwable
+
+object Breaks:
+  private val breakException = new BreakControl
+
+  def breakable(op: => Unit): Unit =
+    try op catch { case ex: BreakControl if ex eq breakException => }
+
+  def break(): Nothing = throw breakException
+
+object A:
+  val n = foo("hello")
+  def foo(s: String): Int =
+    val len = s.length
+    var i = 0
+
+    while (i < len) {
+      Breaks.breakable {
+        val c = s.charAt(i)
+
+        if c == '\n' then Breaks.break()
+      }
+      i += 1
+    }
+
+    i