From 2a204977d45a97424b46492308167d1668f4882c Mon Sep 17 00:00:00 2001
From: Som Snytt <som.snytt@gmail.com>
Date: Fri, 25 Mar 2022 15:48:55 -0700
Subject: [PATCH] Refrain from adding ctor to class from ct.sym

---
 .../scala/tools/nsc/settings/ScalaSettings.scala         | 2 +-
 .../tools/nsc/symtab/classfile/ClassfileParser.scala     | 6 +++++-
 test/files/neg/t12565.check                              | 4 ++++
 test/files/neg/t12565.scala                              | 9 +++++++++
 4 files changed, 19 insertions(+), 2 deletions(-)
 create mode 100644 test/files/neg/t12565.check
 create mode 100644 test/files/neg/t12565.scala

diff --git a/src/compiler/scala/tools/nsc/settings/ScalaSettings.scala b/src/compiler/scala/tools/nsc/settings/ScalaSettings.scala
index 8e6ac5db2e04..1a5587960a54 100644
--- a/src/compiler/scala/tools/nsc/settings/ScalaSettings.scala
+++ b/src/compiler/scala/tools/nsc/settings/ScalaSettings.scala
@@ -90,7 +90,7 @@ trait ScalaSettings extends StandardScalaSettings with Warnings { _: MutableSett
       // TODO validate release <= java.specification.version
     }
   } withAbbreviation "--release"
-  def releaseValue: Option[String] = Option(release.value).filter(_ != "")
+  def releaseValue: Option[String] = Option(release.value).filter(_ != "")  // release.valueSetByUser
 
   /**
    * -X "Advanced" settings
diff --git a/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala b/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
index da93a90d72c1..0c627299ca52 100644
--- a/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
+++ b/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
@@ -549,7 +549,11 @@ abstract class ClassfileParser(reader: ReusableInstance[ReusableDataReader]) {
       val needsConstructor = (
            !sawPrivateConstructor
         && !(instanceScope containsName nme.CONSTRUCTOR)
-        && ((sflags & INTERFACE) == 0 || (sflags | JAVA_ANNOTATION) != 0)
+        && ((sflags & INTERFACE) == 0 || (sflags & JAVA_ANNOTATION) != 0)
+        && {
+          val isSig = file.name.endsWith(".sig")
+          !isSig
+        }
       )
       if (needsConstructor)
         instanceScope enter clazz.newClassConstructor(NoPosition)
diff --git a/test/files/neg/t12565.check b/test/files/neg/t12565.check
new file mode 100644
index 000000000000..b67443b9b545
--- /dev/null
+++ b/test/files/neg/t12565.check
@@ -0,0 +1,4 @@
+t12565.scala:5: error: java.time.Instant does not have a constructor
+  def f = new java.time.Instant
+          ^
+1 error
diff --git a/test/files/neg/t12565.scala b/test/files/neg/t12565.scala
new file mode 100644
index 000000000000..6336f90a4dd4
--- /dev/null
+++ b/test/files/neg/t12565.scala
@@ -0,0 +1,9 @@
+// scalac: -Werror --release 8
+// javaVersion: 9+
+
+class C {
+  def f = new java.time.Instant
+}
+object Test extends App {
+  println(new C().f)
+}