When run with -XX:+UseNullableValueFlattening, test compiler/valhalla/inlinetypes/TestValueConstruction.java crashes with the following message:

# Internal Error (/valhalla/open/src/hotspot/share/opto/inlinetypenode.cpp:524), p
id=1424246, tid=1424262
# assert(!needs_atomic_access) failed: Atomic access in non-atomic container
#
# JRE version: Java(TM) SE Runtime Environment (25.0) (slowdebug build 25-lworld5ea-LTS-2025-03-28-1300093.fred...)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (slowdebug 25-lworld5ea-LTS-2025-03-28-1300093.fred..., mixed mode, tiered, com
pressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0x117ef87] InlineTypeNode::load(GraphKit*, Node*, Node*, ciInstanceKlass*, GrowableArray<ciType*>&, int, un
signed long)+0x19d
#


Stack trace is:

Current thread (0x0000740e142827c0): JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=1424262, stack(0x0000740ded400000,0x0000740ded500000) (1024K)]


Current CompileTask:
C2:55280 1057 b 4 compiler.valhalla.inlinetypes.TestValueConstruction$MyValue9::<init> (27 bytes)

Stack: [0x0000740ded400000,0x0000740ded500000], sp=0x0000740ded4fc5c0, free space=1009k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x117ef87] InlineTypeNode::load(GraphKit*, Node*, Node*, ciInstanceKlass*, GrowableArray<ciType*>&, int, unsigned long)+0x19d (inlinetypenode.cpp:524)
V [libjvm.so+0x1184362] InlineTypeNode::make_from_oop_impl(GraphKit*, Node*, ciInlineKlass*, bool, GrowableArray<ciType*>&, bool)+0x53e (inlinetypenode.cpp:1298)
V [libjvm.so+0x1183e0b] InlineTypeNode::make_from_oop(GraphKit*, Node*, ciInlineKlass*, bool, bool)+0x93 (inlinetypenode.cpp:1228)
V [libjvm.so+0x1815f60] Parse::Parse(JVMState*, ciMethod*, float)+0x10b6 (parse1.cpp:627)
V [libjvm.so+0xb70619] ParseGenerator::generate(JVMState*)+0x187 (callGenerator.cpp:98)
V [libjvm.so+0xccb5bf] Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x137f (compile.cpp:811)
V [libjvm.so+0xb6dce2] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x482 (c2compiler.cpp:142)
V [libjvm.so+0xcf6313] CompileBroker::invoke_compiler_on_method(CompileTask*)+0xdbf (compileBroker.cpp:2331)
V [libjvm.so+0xcf4766] CompileBroker::compiler_thread_loop()+0x558 (compileBroker.cpp:1975)
V [libjvm.so+0xd1689f] CompilerThread::thread_entry(JavaThread*, JavaThread*)+0x89 (compilerThread.cpp:67)
V [libjvm.so+0x11fee48] JavaThread::thread_main_inner()+0x1a6 (javaThread.cpp:777)
V [libjvm.so+0x11fec9f] JavaThread::run()+0x1d7 (javaThread.cpp:762)
V [libjvm.so+0x1aca0f1] Thread::call_run()+0x1b9 (thread.cpp:231)
V [libjvm.so+0x17d438b] thread_native_entry(Thread*)+0x1f5 (os_linux.cpp:877)
C [libc.so.6+0x9caa4]