Migrate Markdown Adjustments - #20
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``` ... ``` for existing ```...```, it will be translated to the above format as well.
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Fix scala#22628 Super call like `super.m()` were emitted with `invokespecial` where owner = `fun.symbol.owner` (the method declaration owner). However, that is wrong for some inherited Java members: the declaration owner can be less accessible than the direct superclass at the Scala call site. In that case it causes `IllegalAccessError` at runtime. This aligns with the normal call behavior, see: scala@fa42b81 **example** In the example below, `fun.symbol.owner` for `super.close()` is `InnerServerCallBase` (where `close` is declared) that is not accessible from `mycode` package. ```scala // mylib/InnerServerCallBase.java (package-private) package mylib; abstract class InnerServerCallBase implements ServerCall { @OverRide public void close() { System.out.println("InnerServerCallBase.close"); } } // mylib/PublicServerCallBase.java package mylib; public abstract class PublicServerCallBase extends InnerServerCallBase {} // mycode/MyServerCall.scala package mycode class MyServerCall extends mylib.PublicServerCallBase: override def close(): Unit = println("MyServerCall.close") super.close() ``` As a result, Scala3 emits the following Java bytecode where `invokespecial` on non-accessible class method. And it causes `IllegalAccessError` at runtime. Scala 3 (before): ```java 0: getstatic #18 // Field scala/Predef$.MODULE$:Lscala/Predef$; 3: ldc #20 // String MyServerCall.close 5: invokevirtual #24 // Method scala/Predef$.println:(Ljava/lang/Object;)V 8: aload_0 9: invokespecial #28 // Method mylib/InnerServerCallBase.close:()V 12: return ``` We should generate `invokespecial` on the call-site qualifier type instead, like Scala 2.13 emits. Scala 2.13 ``` 0: getstatic #16 // Field scala/Predef$.MODULE$:Lscala/Predef$; 3: ldc #18 // String MyServerCall.close 5: invokevirtual #22 // Method scala/Predef$.println:(Ljava/lang/Object;)V 8: aload_0 9: invokespecial #24 // Method mylib/PublicServerCallBase.close:()V 12: return ``` This commit fixes the issue by using call-site qualifier type for invokespecial on super call.
cheeseng
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Mar 7, 2026
Fix scala#22628 scala#24084 as well ? Super call like `super.m()` were emitted with `invokespecial` where owner = `fun.symbol.owner` (the method declaration owner). However, that is wrong for some inherited Java members: the declaration owner can be less accessible than the direct superclass at the Scala call site. In that case it causes `IllegalAccessError` at runtime. This aligns with the normal call behavior, see: scala@fa42b81 **example** In the example below, `fun.symbol.owner` for `super.close()` is `InnerServerCallBase` (where `close` is declared) that is not accessible from `mycode` package. ```scala // mylib/InnerServerCallBase.java (package-private) package mylib; abstract class InnerServerCallBase implements ServerCall { @OverRide public void close() { System.out.println("InnerServerCallBase.close"); } } // mylib/PublicServerCallBase.java package mylib; public abstract class PublicServerCallBase extends InnerServerCallBase {} // mycode/MyServerCall.scala package mycode class MyServerCall extends mylib.PublicServerCallBase: override def close(): Unit = println("MyServerCall.close") super.close() ``` As a result, Scala3 emits the following Java bytecode where `invokespecial` on non-accessible class method. And it causes `IllegalAccessError` at runtime. Scala 3 (before): ```java 0: getstatic #18 // Field scala/Predef$.MODULE$:Lscala/Predef$; 3: ldc #20 // String MyServerCall.close 5: invokevirtual #24 // Method scala/Predef$.println:(Ljava/lang/Object;)V 8: aload_0 9: invokespecial #28 // Method mylib/InnerServerCallBase.close:()V 12: return ``` We should generate `invokespecial` on the call-site qualifier type instead, like Scala 2.13 emits. Scala 2.13 ``` 0: getstatic #16 // Field scala/Predef$.MODULE$:Lscala/Predef$; 3: ldc #18 // String MyServerCall.close 5: invokevirtual #22 // Method scala/Predef$.println:(Ljava/lang/Object;)V 8: aload_0 9: invokespecial #24 // Method mylib/PublicServerCallBase.close:()V 12: return ``` This commit fixes the issue by using call-site qualifier type for invokespecial on super call. --- Huge thanks to @migesok for creating a reproducible example 🙌 https://github.com/migesok/scala3-bug-super-IllegalAccessError
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for existing
..., it will be translated to the above format as well.