Kotlin: Compile with -Werror, and fix warnings

Author: igfoo

java/kotlin-extractor/build.py

@@ -86,7 +86,8 @@ def compile_to_dir(srcs, classpath, java_classpath, output):
     run_process([kotlinc,
                  # kotlinc can default to 256M, which isn't enough when we are extracting the build
                  '-J-Xmx2G',
-                 '-Xopt-in=kotlin.RequiresOptIn',
+                 '-Werror',
+                 '-opt-in=kotlin.RequiresOptIn',
                  '-d', output,
                  '-module-name', 'codeql-kotlin-extractor',
                  '-no-reflect', '-no-stdlib',

java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt

@@ -2582,8 +2582,8 @@ open class KotlinFileExtractor(
                     indexVarDecl.initializer?.let { indexVarInitializer ->
                         (e.statements[2] as? IrCall)?.let { arraySetCall ->
                             if (isFunction(arraySetCall.symbol.owner, "kotlin", "(some array type)", { isArrayType(it) }, "set")) {
-                                val updateRhs = arraySetCall.getValueArgument(1)
-                                if (updateRhs == null) {
+                                val updateRhs0 = arraySetCall.getValueArgument(1)
+                                if (updateRhs0 == null) {
                                     logger.errorElement("Update RHS not found", e)
                                     return false
                                 }
@@ -2596,7 +2596,7 @@ open class KotlinFileExtractor(
                                             receiverVal -> receiverVal.symbol.owner == arrayVarDecl.symbol.owner
                                         } ?: false
                                     },
-                                    updateRhs
+                                    updateRhs0
                                 )?.let { updateRhs ->
                                     val origin = e.origin
                                     if (origin == null) {
@@ -3421,15 +3421,11 @@ open class KotlinFileExtractor(
 
     data class ReceiverInfo(val receiver: IrExpression, val type: IrType, val field: Label<DbField>, val indexOffset: Int)
 
-    private fun makeReceiverInfo(callableReferenceExpr: IrCallableReference<out IrSymbol>, receiver: IrExpression?, indexOffset: Int): ReceiverInfo? {
+    private fun makeReceiverInfo(receiver: IrExpression?, indexOffset: Int): ReceiverInfo? {
         if (receiver == null) {
             return null
         }
         val type = receiver.type
-        if (type == null) {
-            logger.warnElement("Receiver has no type", callableReferenceExpr)
-            return null
-        }
         val field: Label<DbField> = tw.getFreshIdLabel()
         return ReceiverInfo(receiver, type, field, indexOffset)
     }
@@ -3442,8 +3438,8 @@ open class KotlinFileExtractor(
         : GeneratedClassHelper(locId, ids) {
 
         // Only one of the receivers can be non-null, but we defensively handle the case when both are null anyway
-        private val dispatchReceiverInfo = makeReceiverInfo(callableReferenceExpr, callableReferenceExpr.dispatchReceiver, 0)
-        private val extensionReceiverInfo = makeReceiverInfo(callableReferenceExpr, callableReferenceExpr.extensionReceiver, if (dispatchReceiverInfo == null) 0 else 1)
+        private val dispatchReceiverInfo = makeReceiverInfo(callableReferenceExpr.dispatchReceiver, 0)
+        private val extensionReceiverInfo = makeReceiverInfo(callableReferenceExpr.extensionReceiver, if (dispatchReceiverInfo == null) 0 else 1)
 
         fun extractReceiverField() {
             val firstAssignmentStmtIdx = 1

java/kotlin-extractor/src/main/kotlin/KotlinUsesExtractor.kt

@@ -327,7 +327,7 @@ open class KotlinUsesExtractor(
             return f
         return globalExtensionState.syntheticToRealFunctionMap.getOrPut(f) {
             val result = replacementClass.declarations.findSubType<IrSimpleFunction> { replacementDecl ->
-                replacementDecl is IrSimpleFunction && replacementDecl.name == f.name && replacementDecl.valueParameters.size == f.valueParameters.size && replacementDecl.valueParameters.zip(f.valueParameters).all {
+                replacementDecl.name == f.name && replacementDecl.valueParameters.size == f.valueParameters.size && replacementDecl.valueParameters.zip(f.valueParameters).all {
                     erase(it.first.type) == erase(it.second.type)
                 }
             }