JVM_IR: fix synthetic accessor generation (again)

Turns out private inline functions *can* be called from other classes.

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

@@ -435,11 +435,13 @@ internal class SyntheticAccessorLowering(val context: JvmBackendContext) : IrEle
 
     private fun IrDeclaration.getAccessContext(withSuper: Boolean): IrDeclarationContainer? = when {
         this is IrDeclarationContainer -> this
-        // Accesses from public inline functions can actually be anywhere. For protected inline functions
-        // calling methods on `super` we need an accessor to satisfy INVOKESPECIAL constraints.
-        this is IrFunction && isInline && !visibility.isPrivate && (withSuper || !visibility.isProtected) -> null
         // For inline lambdas, we can navigate to the only call site directly.
         this in inlineLambdaToCallSite -> inlineLambdaToCallSite[this]?.getAccessContext(withSuper)
+        // Accesses from inline functions can actually be anywhere; even private inline functions can be
+        // inlined into a different class, e.g. a callable reference. For protected inline functions
+        // calling methods on `super` we also need an accessor to satisfy INVOKESPECIAL constraints.
+        // TODO scan nested classes for calls to private inline functions?
+        this is IrFunction && isInline -> null
         else -> (parent as? IrDeclaration)?.getAccessContext(withSuper)
     }
 

compiler/testData/codegen/box/syntheticAccessors/inlineInOtherClass.kt

@@ -0,0 +1,7 @@
+class A {
+    private inline fun f() = g()
+    private fun g() = "OK"
+    fun h() = { f() }
+}
+
+fun box() = A().h()()

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -24922,6 +24922,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             runTest("compiler/testData/codegen/box/syntheticAccessors/inline.kt");
         }
 
+        @TestMetadata("inlineInOtherClass.kt")
+        public void testInlineInOtherClass() throws Exception {
+            runTest("compiler/testData/codegen/box/syntheticAccessors/inlineInOtherClass.kt");
+        }
+
         @TestMetadata("jvmField.kt")
         public void testJvmField() throws Exception {
             runTest("compiler/testData/codegen/box/syntheticAccessors/jvmField.kt");

compiler/tests/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -24922,6 +24922,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
             runTest("compiler/testData/codegen/box/syntheticAccessors/inline.kt");
         }
 
+        @TestMetadata("inlineInOtherClass.kt")
+        public void testInlineInOtherClass() throws Exception {
+            runTest("compiler/testData/codegen/box/syntheticAccessors/inlineInOtherClass.kt");
+        }
+
         @TestMetadata("jvmField.kt")
         public void testJvmField() throws Exception {
             runTest("compiler/testData/codegen/box/syntheticAccessors/jvmField.kt");

compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBlackBoxCodegenTestGenerated.java

@@ -23822,6 +23822,11 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             runTest("compiler/testData/codegen/box/syntheticAccessors/inline.kt");
         }
 
+        @TestMetadata("inlineInOtherClass.kt")
+        public void testInlineInOtherClass() throws Exception {
+            runTest("compiler/testData/codegen/box/syntheticAccessors/inlineInOtherClass.kt");
+        }
+
         @TestMetadata("jvmField.kt")
         public void testJvmField() throws Exception {
             runTest("compiler/testData/codegen/box/syntheticAccessors/jvmField.kt");

js/js.tests/test/org/jetbrains/kotlin/js/test/ir/semantics/IrJsCodegenBoxTestGenerated.java

@@ -19052,6 +19052,11 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/syntheticAccessors/inline.kt");
         }
 
+        @TestMetadata("inlineInOtherClass.kt")
+        public void testInlineInOtherClass() throws Exception {
+            runTest("compiler/testData/codegen/box/syntheticAccessors/inlineInOtherClass.kt");
+        }
+
         @TestMetadata("kt10047.kt")
         public void testKt10047() throws Exception {
             runTest("compiler/testData/codegen/box/syntheticAccessors/kt10047.kt");

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -20207,6 +20207,11 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/syntheticAccessors/inline.kt");
         }
 
+        @TestMetadata("inlineInOtherClass.kt")
+        public void testInlineInOtherClass() throws Exception {
+            runTest("compiler/testData/codegen/box/syntheticAccessors/inlineInOtherClass.kt");
+        }
+
         @TestMetadata("kt10047.kt")
         public void testKt10047() throws Exception {
             runTest("compiler/testData/codegen/box/syntheticAccessors/kt10047.kt");