Re: static vs. default interface methods and inheritance VM/javac issues
On 13/09/2013 10:37, Peter Levart wrote: Karen, I filed a bug, but don't have the bug ID yet. Will let you know when I get it. I found it, and moved it into the JDK project as: 8024836: static vs. default interface methods and inheritance - VM crash -Alan.
Re: static vs. default interface methods and inheritance VM/javac issues
Hi,
Thanks Karen and Peter.
FWIW my interpretation is that javac is doing the right thing. The bytecode
generated is an invokeinterface DefaultStaticMethodTest$C.m(). This looks
consistent with the other bytecodes generated for calls to methods of anonymous
classes implementing an interface. There should be no ambiguity in the program
since static interface methods are not inherited, so javac is right in
accepting it.
cheers
/Joel
On Sep 12, 2013, at 8:23 PM, Karen Kinnear karen.kinn...@oracle.com wrote:
Thank you, we really appreciate all testing.
I have a fix in a prototype in the vm for this. Let me know if you want an
early patch.
Or you can just file a bug and that way you'll know when the fix is
officially in the tree.
thanks,
Karen
On Sep 12, 2013, at 10:59 AM, Peter Levart wrote:
Hi,
While testing behavior of reflection on default and static interface
methods, using self-built JDK from latest tip of jdk8/tl, I found:
The following program:
public class DefaultVsStaticInterfaceMethodTest {
public interface A {
default void m() {
System.out.println(A.m() called);
}
}
public interface B {
static void m() {
System.out.println(B.m() called);
}
}
public interface C extends A, B {
}
public static void main(String[] args) throws Exception {
C c = new C() {};
c.m();
}
}
...compiles, but gives a runtime error:
Exception in thread main java.lang.AbstractMethodError: Conflicting
default methods: DefaultVsStaticInterfaceMethodTest$A.m
DefaultVsStaticInterfaceMethodTest$B.m
at
DefaultVsStaticInterfaceMethodTest$1.m(DefaultVsStaticInterfaceMethodTest.java)
at
DefaultVsStaticInterfaceMethodTest.main(DefaultVsStaticInterfaceMethodTest.java:28)
A slightly modified program: C extends A, B replaced with C extends B, A:
http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/DefaultVsStaticInterfaceMethodTest.java
...also compiles, but crashes the VM when run:
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x7fd4d5020bf9, pid=9964, tid=140552419804928
#
# JRE version: OpenJDK Runtime Environment (8.0) (build
1.8.0-internal-peter_2013_09_12_16_29-b00)
# Java VM: OpenJDK 64-Bit Server VM (25.0-b48 mixed mode linux-amd64
compressed oops)
# Problematic frame:
# j DefaultVsStaticInterfaceMethodTest.main([Ljava/lang/String;)V+9
#
# Failed to write core dump. Core dumps have been disabled. To enable core
dumping, try ulimit -c unlimited before starting Java again
#
# An error report file with more information is saved as:
# /home/peter/work/git/jdk8-tl/out/production/test/hs_err_pid9964.log
#
# If you would like to submit a bug report, please visit:
# http://bugreport.sun.com/bugreport/crash.jsp
#
Aborted (core dumped)
Here's the hs_err_pid file:
http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/hs_err_pid9964.log
Regards, Peter
Re: static vs. default interface methods and inheritance VM/javac issues
On 09/13/2013 11:05 AM, Joel Borggrén-Franck wrote:
Hi,
Thanks Karen and Peter.
FWIW my interpretation is that javac is doing the right thing. The bytecode generated is
an invokeinterface DefaultStaticMethodTest$C.m(). This looks consistent with
the other bytecodes generated for calls to methods of anonymous classes implementing an
interface. There should be no ambiguity in the program since static interface methods are
not inherited, so javac is right in accepting it.
I think that too. In that case even the AbstractMethodError is incorrect
VM behaviour. And the order of C extends B, A vs. C extends A, B
should not effect the behaviour.
Karen, I filed a bug, but don't have the bug ID yet. Will let you know
when I get it.
Regards, Peter
cheers /Joel
On Sep 12, 2013, at 8:23 PM, Karen Kinnear karen.kinn...@oracle.com
wrote:
Thank you, we really appreciate all testing.
I have a fix in a prototype in the vm for this. Let me know if you want an
early patch.
Or you can just file a bug and that way you'll know when the fix is officially
in the tree.
thanks,
Karen
On Sep 12, 2013, at 10:59 AM, Peter Levart wrote:
Hi,
While testing behavior of reflection on default and static interface methods,
using self-built JDK from latest tip of jdk8/tl, I found:
The following program:
public class DefaultVsStaticInterfaceMethodTest {
public interface A {
default void m() {
System.out.println(A.m() called);
}
}
public interface B {
static void m() {
System.out.println(B.m() called);
}
}
public interface C extends A, B {
}
public static void main(String[] args) throws Exception {
C c = new C() {};
c.m();
}
}
...compiles, but gives a runtime error:
Exception in thread main java.lang.AbstractMethodError: Conflicting default
methods: DefaultVsStaticInterfaceMethodTest$A.m DefaultVsStaticInterfaceMethodTest$B.m
at
DefaultVsStaticInterfaceMethodTest$1.m(DefaultVsStaticInterfaceMethodTest.java)
at
DefaultVsStaticInterfaceMethodTest.main(DefaultVsStaticInterfaceMethodTest.java:28)
A slightly modified program: C extends A, B replaced with C extends B, A:
http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/DefaultVsStaticInterfaceMethodTest.java
...also compiles, but crashes the VM when run:
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x7fd4d5020bf9, pid=9964, tid=140552419804928
#
# JRE version: OpenJDK Runtime Environment (8.0) (build
1.8.0-internal-peter_2013_09_12_16_29-b00)
# Java VM: OpenJDK 64-Bit Server VM (25.0-b48 mixed mode linux-amd64 compressed
oops)
# Problematic frame:
# j DefaultVsStaticInterfaceMethodTest.main([Ljava/lang/String;)V+9
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try
ulimit -c unlimited before starting Java again
#
# An error report file with more information is saved as:
# /home/peter/work/git/jdk8-tl/out/production/test/hs_err_pid9964.log
#
# If you would like to submit a bug report, please visit:
# http://bugreport.sun.com/bugreport/crash.jsp
#
Aborted (core dumped)
Here's the hs_err_pid file:
http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/hs_err_pid9964.log
Regards, Peter
static vs. default interface methods and inheritance VM/javac issues
Hi,
While testing behavior of reflection on default and static interface
methods, using self-built JDK from latest tip of jdk8/tl, I found:
The following program:
public class DefaultVsStaticInterfaceMethodTest {
public interface A {
default void m() {
System.out.println(A.m() called);
}
}
public interface B {
static void m() {
System.out.println(B.m() called);
}
}
public interface C extends A, B {
}
public static void main(String[] args) throws Exception {
C c = new C() {};
c.m();
}
}
...compiles, but gives a runtime error:
Exception in thread main java.lang.AbstractMethodError: Conflicting
default methods: DefaultVsStaticInterfaceMethodTest$A.m
DefaultVsStaticInterfaceMethodTest$B.m
at
DefaultVsStaticInterfaceMethodTest$1.m(DefaultVsStaticInterfaceMethodTest.java)
at
DefaultVsStaticInterfaceMethodTest.main(DefaultVsStaticInterfaceMethodTest.java:28)
A slightly modified program: C extends A, B replaced with C extends
B, A:
http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/DefaultVsStaticInterfaceMethodTest.java
...also compiles, but crashes the VM when run:
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x7fd4d5020bf9, pid=9964, tid=140552419804928
#
# JRE version: OpenJDK Runtime Environment (8.0) (build
1.8.0-internal-peter_2013_09_12_16_29-b00)
# Java VM: OpenJDK 64-Bit Server VM (25.0-b48 mixed mode linux-amd64
compressed oops)
# Problematic frame:
# j DefaultVsStaticInterfaceMethodTest.main([Ljava/lang/String;)V+9
#
# Failed to write core dump. Core dumps have been disabled. To enable
core dumping, try ulimit -c unlimited before starting Java again
#
# An error report file with more information is saved as:
# /home/peter/work/git/jdk8-tl/out/production/test/hs_err_pid9964.log
#
# If you would like to submit a bug report, please visit:
# http://bugreport.sun.com/bugreport/crash.jsp
#
Aborted (core dumped)
Here's the hs_err_pid file:
http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/hs_err_pid9964.log
Regards, Peter
Re: static vs. default interface methods and inheritance VM/javac issues
Thank you, we really appreciate all testing.
I have a fix in a prototype in the vm for this. Let me know if you want an
early patch.
Or you can just file a bug and that way you'll know when the fix is officially
in the tree.
thanks,
Karen
On Sep 12, 2013, at 10:59 AM, Peter Levart wrote:
Hi,
While testing behavior of reflection on default and static interface methods,
using self-built JDK from latest tip of jdk8/tl, I found:
The following program:
public class DefaultVsStaticInterfaceMethodTest {
public interface A {
default void m() {
System.out.println(A.m() called);
}
}
public interface B {
static void m() {
System.out.println(B.m() called);
}
}
public interface C extends A, B {
}
public static void main(String[] args) throws Exception {
C c = new C() {};
c.m();
}
}
...compiles, but gives a runtime error:
Exception in thread main java.lang.AbstractMethodError: Conflicting default
methods: DefaultVsStaticInterfaceMethodTest$A.m
DefaultVsStaticInterfaceMethodTest$B.m
at
DefaultVsStaticInterfaceMethodTest$1.m(DefaultVsStaticInterfaceMethodTest.java)
at
DefaultVsStaticInterfaceMethodTest.main(DefaultVsStaticInterfaceMethodTest.java:28)
A slightly modified program: C extends A, B replaced with C extends B, A:
http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/DefaultVsStaticInterfaceMethodTest.java
...also compiles, but crashes the VM when run:
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x7fd4d5020bf9, pid=9964, tid=140552419804928
#
# JRE version: OpenJDK Runtime Environment (8.0) (build
1.8.0-internal-peter_2013_09_12_16_29-b00)
# Java VM: OpenJDK 64-Bit Server VM (25.0-b48 mixed mode linux-amd64
compressed oops)
# Problematic frame:
# j DefaultVsStaticInterfaceMethodTest.main([Ljava/lang/String;)V+9
#
# Failed to write core dump. Core dumps have been disabled. To enable core
dumping, try ulimit -c unlimited before starting Java again
#
# An error report file with more information is saved as:
# /home/peter/work/git/jdk8-tl/out/production/test/hs_err_pid9964.log
#
# If you would like to submit a bug report, please visit:
# http://bugreport.sun.com/bugreport/crash.jsp
#
Aborted (core dumped)
Here's the hs_err_pid file:
http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/hs_err_pid9964.log
Regards, Peter
