Suppress K2 specific warnings in the codebase

^KT-62472

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/InventNamesForLocalClasses.kt

@@ -73,6 +73,7 @@ abstract class InventNamesForLocalClasses(
             val isLocal = parent is IrFile && declaration.isAnonymousObject
             if (!isLocal) return processClass(declaration, data)
 
+            @Suppress("USELESS_CAST") // K2 warning suppression, TODO: KT-62472
             val enclosingName = (parent as IrFile).name.removeSuffix(".kt").plus("Kt").capitalizeAsciiOnly()
             processClass(declaration, data.copy(enclosingName = enclosingName, isLocal = true))
         }

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/dce/UsefulDeclarationProcessor.kt

@@ -105,6 +105,7 @@ abstract class UsefulDeclarationProcessor(
         addReachabilityInfoIfNeeded(from, this, description, isContagiousOverridableDeclaration)
 
         if (isContagiousOverridableDeclaration) {
+            @Suppress("USELESS_CAST") // K2 warning suppression, TODO: KT-62472
             contagiousReachableDeclarations.add(this as IrOverridableDeclaration<*>)
         }
 

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/KotlinSourceFileMetadata.kt

@@ -52,6 +52,7 @@ open class KotlinSourceFileMap<out T>(files: Map<KotlinLibraryFile, Map<KotlinSo
     operator fun get(libFile: KotlinLibraryFile, sourceFile: KotlinSourceFile): T? = get(libFile)?.get(sourceFile)
 }
 
+@Suppress("DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE") // K2 warning suppression, TODO: KT-62472
 class KotlinSourceFileMutableMap<T>(
     private val files: MutableMap<KotlinLibraryFile, MutableMap<KotlinSourceFile, T>> = hashMapOf()
 ) : KotlinSourceFileMap<T>(files) {

compiler/ir/backend.jvm/lower/src/org/jetbrains/kotlin/backend/jvm/lower/AddContinuationLowering.kt

@@ -262,6 +262,7 @@ private class AddContinuationLowering(context: JvmBackendContext) : SuspendLower
                     var cursor = irFunction.parentAsClass.parent
                     while (cursor is IrClass) {
                         if (cursor == param.parent) return true
+                        @Suppress("USELESS_CAST") // K2 warning suppression, TODO: KT-62472
                         cursor = (cursor as IrClass).parent
                     }
                     return false

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/IrUtils.kt

@@ -350,6 +350,7 @@ val IrDeclaration.parentAsClass: IrClass
 fun IrElement.getPackageFragment(): IrPackageFragment? =
     this as? IrPackageFragment ?: (this as? IrDeclaration)?.getPackageFragment()
 
+@Suppress("NO_TAIL_CALLS_FOUND", "NON_TAIL_RECURSIVE_CALL") // K2 warning suppression, TODO: KT-62472
 tailrec fun IrDeclaration.getPackageFragment(): IrPackageFragment {
     val parent = this.parent
     return parent as? IrPackageFragment
@@ -1547,4 +1548,4 @@ private fun Any?.toIrConstOrNull(irType: IrType, startOffset: Int = SYNTHETIC_OF
 
 fun Any?.toIrConst(irType: IrType, startOffset: Int = SYNTHETIC_OFFSET, endOffset: Int = SYNTHETIC_OFFSET): IrConst<*> =
     toIrConstOrNull(irType, startOffset, endOffset)
-        ?: throw UnsupportedOperationException("Unsupported const element type ${irType.makeNotNull().render()}")
+        ?: throw UnsupportedOperationException("Unsupported const element type ${irType.makeNotNull().render()}")