Build: enable Werror for all compileJava tasks

build.gradle.kts

@@ -443,6 +443,12 @@ allprojects {
         project.configureShadowJarSubstitutionInCompileClasspath()
     }
 
+    tasks.withType<JavaCompile> {
+        options.compilerArgs.add("-Xlint:deprecation")
+        options.compilerArgs.add("-Xlint:unchecked")
+        options.compilerArgs.add("-Werror")
+    }
+
     val commonCompilerArgs = listOfNotNull(
         "-Xopt-in=kotlin.RequiresOptIn",
         "-progressive".takeIf { hasProperty("test.progressive.mode") }

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -1242,6 +1242,7 @@ public interface Errors {
             }
         }
 
+        @SuppressWarnings("unchecked")
         private static void initializeNameAndRenderer(DiagnosticFactoryToRendererMap diagnosticToRendererMap, String name, DiagnosticFactory<?> factory) {
             factory.initializeName(name);
             factory.setDefaultRenderer((DiagnosticRenderer) diagnosticToRendererMap.get(factory));

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -1090,10 +1090,12 @@ public class DefaultErrorMessages {
     }
 
     // Those methods are needed to fix problems with java type system and kotlin variance
+    @SuppressWarnings("unchecked")
     public static DiagnosticParameterRenderer<Map<Incompatible<MemberDescriptor>, Collection<MemberDescriptor>>> adaptGenerics1(DiagnosticParameterRenderer<Map<Incompatible<? extends MemberDescriptor>, ? extends Collection<? extends MemberDescriptor>>> renderer) {
         return (obj, renderingContext) -> renderer.render((Map)obj, renderingContext);
     }
 
+    @SuppressWarnings("unchecked")
     public static DiagnosticParameterRenderer<List<Pair<MemberDescriptor, Map<Incompatible<MemberDescriptor>, Collection<MemberDescriptor>>>>> adaptGenerics2(DiagnosticParameterRenderer<List<? extends Pair<? extends MemberDescriptor, ? extends Map<ExpectActualCompatibility.Incompatible<? extends MemberDescriptor>, ? extends Collection<? extends MemberDescriptor>>>>> renderer) {
         return (obj, renderingContext) -> renderer.render((List)obj, renderingContext);
     }