On Thu, 3 Jul 2025 18:41:27 GMT, Chen Liang <li...@openjdk.org> wrote:
>> Unsafe throws IAE for misusing static vs instance fields, and it's revealed >> that AtomicXxxFieldUpdaters are using this mechanism to reject static >> fields. This is not a good practice, but we can at least document this so we >> don't accidentally introduce problems. > > Chen Liang has updated the pull request incrementally with one additional > commit since the last revision: > > Test to verify observed internal unsafe behaviors src/java.base/share/classes/jdk/internal/misc/Unsafe.java line 3861: > 3859: private native void copySwapMemory0(Object srcBase, long srcOffset, > Object destBase, long destOffset, long bytes, long elemSize); > 3860: private native long objectFieldOffset0(Field f); // throws IAE > 3861: private native long objectFieldOffset1(Class<?> c, String name); // > throws InternalError Ugh; this IE is part of the problem. You could push an IAE into the C++ code for symmetry, or start pushing more IAE logic into the Java code (my preference, but a bigger change perhaps). I can tell you that the original intention of choosing InternalError is to mark places where the caller has a responsibility to make InternalError impossible. InternalError is not intended to trigger further processing; it denotes system failure. test/jdk/jdk/internal/misc/Unsafe/AddressComputationContractTest.java line 69: > 67: assertThrows(NullPointerException.class, () -> > getUnsafe().objectFieldOffset(null, "instanceField")); > 68: assertThrows(NullPointerException.class, () -> > getUnsafe().objectFieldOffset(AddressComputationContractTest.class, null)); > 69: assertThrows(InternalError.class, () -> > getUnsafe().objectFieldOffset(AddressComputationContractTest.class, > "doesNotExist")); This is a malformed test on a malformed API. VirtualMachineError exceptions signal system failure. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/25945#discussion_r2243472376 PR Review Comment: https://git.openjdk.org/jdk/pull/25945#discussion_r2243477795
