Fixed bug in inliner with default args + test

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/FunctionInlining.kt

@@ -448,11 +448,16 @@ private class Inliner(val globalSubstituteMap: MutableMap<DeclarationDescriptor,
              * For simplicity and to produce simpler IR we don't create temporaries for every immutable variable,
              * not only for those referring to inlinable lambdas.
              */
-            if (it.isInlinableLambdaArgument || it.isImmutableVariableLoad) {
+            if (it.isInlinableLambdaArgument) {
                 substituteMap[parameterDescriptor] = it.argumentExpression
                 return@forEach
             }
 
+            if (it.isImmutableVariableLoad) {
+                substituteMap[parameterDescriptor] = it.argumentExpression.transform(substitutor, data = null)   // Arguments may reference the previous ones - substitute them.
+                return@forEach
+            }
+
             val newVariable = currentScope.scope.createTemporaryVariable(                   // Create new variable and init it with the parameter expression.
                 irExpression = it.argumentExpression.transform(substitutor, data = null),   // Arguments may reference the previous ones - substitute them.
                 nameHint     = functionDeclaration.descriptor.name.toString(),

backend.native/tests/build.gradle

@@ -2466,6 +2466,11 @@ task inline_changingCapturedLocal(type: RunKonanTest) {
     source = "codegen/inline/changingCapturedLocal.kt"
 }
 
+task inline_defaultArgs(type: RunKonanTest) {
+    goldValue = "42\n"
+    source = "codegen/inline/defaultArgs.kt"
+}
+
 task deserialized_inline0(type: RunKonanTest) {
     source = "serialization/deserialized_inline0.kt"
 }

backend.native/tests/codegen/inline/defaultArgs.kt

@@ -0,0 +1,14 @@
+package codegen.inline.defaultArgs
+
+import kotlin.test.*
+
+class Z
+
+inline fun Z.foo(x: Int = 42, y: Int = x) {
+    println(y)
+}
+
+@Test fun runTest() {
+    val z = Z()
+    z.foo()
+}