From a722358a0944e788c8aef15dac0af19e811d4761 Mon Sep 17 00:00:00 2001
From: EnzeXing <enzexing12@gmail.com>
Date: Tue, 20 Aug 2024 12:52:07 -0400
Subject: [PATCH 1/2] Fix uninitializing fields when evaluating a cached
 constructor call

---
 .../src/dotty/tools/dotc/transform/init/Objects.scala    | 1 -
 tests/init-global/pos/cache-constructor.scala            | 9 +++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)
 create mode 100644 tests/init-global/pos/cache-constructor.scala

diff --git a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
index 1ceb8d4472a3..892cd3ce8b06 100644
--- a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
+++ b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
@@ -950,7 +950,6 @@ class Objects(using Context @constructorOnly):
 
         val instance = OfClass(klass, outerWidened, ctor, args.map(_.value), envWidened)
         callConstructor(instance, ctor, args)
-        instance
 
     case ValueSet(values) =>
       values.map(ref => instantiate(ref, klass, ctor, args)).join
diff --git a/tests/init-global/pos/cache-constructor.scala b/tests/init-global/pos/cache-constructor.scala
new file mode 100644
index 000000000000..f7af30f32516
--- /dev/null
+++ b/tests/init-global/pos/cache-constructor.scala
@@ -0,0 +1,9 @@
+class Bar:
+    var f: Int = 0
+
+object A:
+    val b1 = new Bar()
+    val b2 = new Bar()
+    val b3 = new Bar()
+    b3.f = 1
+    
\ No newline at end of file

From 36b49497186b50febf865a556d338d109f9027a6 Mon Sep 17 00:00:00 2001
From: EnzeXing <enzexing12@gmail.com>
Date: Tue, 20 Aug 2024 14:23:36 -0400
Subject: [PATCH 2/2] Address comment

---
 compiler/src/dotty/tools/dotc/transform/init/Objects.scala | 5 ++++-
 tests/init-global/pos/cache-constructor.scala              | 1 -
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
index 892cd3ce8b06..1050fbe85ef2 100644
--- a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
+++ b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
@@ -908,7 +908,10 @@ class Objects(using Context @constructorOnly):
     Bottom
   }
 
-  /** Handle new expression `new p.C(args)`.
+  /**
+   * Handle new expression `new p.C(args)`.
+   * The actual instance might be cached without running the constructor. 
+   * See tests/init-global/pos/cache-constructor.scala
    *
    * @param outer       The value for `p`.
    * @param klass       The symbol of the class `C`.
diff --git a/tests/init-global/pos/cache-constructor.scala b/tests/init-global/pos/cache-constructor.scala
index f7af30f32516..87769fd5d78a 100644
--- a/tests/init-global/pos/cache-constructor.scala
+++ b/tests/init-global/pos/cache-constructor.scala
@@ -6,4 +6,3 @@ object A:
     val b2 = new Bar()
     val b3 = new Bar()
     b3.f = 1
-    
\ No newline at end of file