Skip VarHandle init when unaligned access is supported (#16664)#16676
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`initializeVarHandle()`. This made VarHandle code reachable even when Unsafe is available, causing Truffle/Polyglot native-image builds to fail with `MethodHandle.linkToStatic` blocklist violations (#16607). Restoring the original Unsafe guard fixes #16607, but also kills Use `isUnaligned()` as the guard instead. On platforms where unaligned access is known (x86, modern ARM), Unsafe already handles multi-byte access fine, so VarHandle isn't needed and VarHandleFactory stays unreachable. On platforms where UNALIGNED is unknown (exactly the case #16207 targets), VarHandle still gets initialized and works as before. Fixes #16607. Tested with the reporter's project (https://github.com/adamdickmeiss/vertx-graalvm-native-image-log4j): - Before: `=== Found 4 compilation blocklist violations ===` BUILD FAILURE - After: No violations, BUILD SUCCESS Co-authored-by: Chris Vest <christianvest_hansen@apple.com>
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initializeVarHandle(). This made VarHandle code reachable even whenUnsafe is available,
causing Truffle/Polyglot native-image builds to fail with
MethodHandle.linkToStaticblocklist violations (#16607).Restoring the original Unsafe guard fixes #16607, but also kills
Use
isUnaligned()as the guard instead. On platforms where unalignedaccess is known (x86, modern ARM), Unsafe already handles multi-byte
access fine, so VarHandle
isn't needed and VarHandleFactory stays unreachable.
On platforms where UNALIGNED is unknown (exactly the case #16207
targets), VarHandle still gets initialized and works as before.
Fixes #16607.
Tested with the reporter's project
(https://github.com/adamdickmeiss/vertx-graalvm-native-image-log4j):
=== Found 4 compilation blocklist violations ===BUILDFAILURE
Co-authored-by: Chris Vest christianvest_hansen@apple.com