From ac40aa63e7430d8ece56c38b3c321383e2e432e5 Mon Sep 17 00:00:00 2001
From: willerf <erfwill@gmail.com>
Date: Fri, 8 Mar 2024 08:36:42 -0500
Subject: [PATCH] suppress warnings in global init checker

---
 .../tools/dotc/transform/init/Checker.scala   |  3 ++-
 .../tools/dotc/transform/init/Objects.scala   | 22 +++++++++++--------
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/transform/init/Checker.scala b/compiler/src/dotty/tools/dotc/transform/init/Checker.scala
index 7cf028c95064..692b3177786d 100644
--- a/compiler/src/dotty/tools/dotc/transform/init/Checker.scala
+++ b/compiler/src/dotty/tools/dotc/transform/init/Checker.scala
@@ -50,7 +50,8 @@ class Checker extends Phase:
         Semantic.checkClasses(classes)(using checkCtx)
 
       if ctx.settings.YcheckInitGlobal.value then
-        Objects.checkClasses(classes)(using checkCtx)
+        val obj = new Objects
+        obj.checkClasses(classes)(using checkCtx)
     }
 
     units0
diff --git a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
index 763b71619de8..39ce09ccfa23 100644
--- a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
+++ b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
@@ -65,7 +65,7 @@ import scala.annotation.constructorOnly
  *     whole-program analysis. However, the check is not modular in terms of project boundaries.
  *
  */
-object Objects:
+class Objects:
 
   // ----------------------------- abstract domain -----------------------------
 
@@ -1734,16 +1734,20 @@ object Objects:
       if cls.isAllOf(Flags.JavaInterface) then Bottom
       else evalType(tref.prefix, thisV, klass, elideObjectAccess = cls.isStatic)
 
+  val mutateErrorSet: mutable.Set[(ClassSymbol, ClassSymbol)] = mutable.Set.empty
   def errorMutateOtherStaticObject(currentObj: ClassSymbol, otherObj: ClassSymbol)(using Trace, Context) =
-    val msg =
-      s"Mutating ${otherObj.show} during initialization of ${currentObj.show}.\n" +
-      "Mutating other static objects during the initialization of one static object is forbidden. " + Trace.show
+    if mutateErrorSet.add((currentObj, otherObj)) then
+      val msg =
+        s"Mutating ${otherObj.show} during initialization of ${currentObj.show}.\n" +
+        "Mutating other static objects during the initialization of one static object is forbidden. " + Trace.show
 
-    report.warning(msg, Trace.position)
+      report.warning(msg, Trace.position)
 
+  val readErrorSet: mutable.Set[(ClassSymbol, ClassSymbol)] = mutable.Set.empty
   def errorReadOtherStaticObject(currentObj: ClassSymbol, otherObj: ClassSymbol)(using Trace, Context) =
-    val msg =
-      "Reading mutable state of " + otherObj.show + " during initialization of " + currentObj.show + ".\n" +
-      "Reading mutable state of other static objects is forbidden as it breaks initialization-time irrelevance. " + Trace.show
+    if readErrorSet.add((currentObj, otherObj)) then
+      val msg =
+        "Reading mutable state of " + otherObj.show + " during initialization of " + currentObj.show + ".\n" +
+        "Reading mutable state of other static objects is forbidden as it breaks initialization-time irrelevance. " + Trace.show
 
-    report.warning(msg, Trace.position)
+      report.warning(msg, Trace.position)