#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (src/hotspot/share/opto/type.cpp:3159), pid=636346, tid=636363
# assert(!instance_klass->maybe_flat_in_array()) failed: cannot be flat
#
# JRE version: Java(TM) SE Runtime Environment (26.0+1) (fastdebug build 26-valhalla+1-196)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 26-valhalla+1-196, mixed mode, tiered, compressed oops, compressed class ptrs, g1 gc, linux-aarch64)
# Problematic frame:
# V [libjvm.so+0x19c5da4] TypePtr::compute_flat_in_array_if_unknown(ciInstanceKlass*, bool, TypePtr::FlatInArray) const+0xc4
#
# Core dump will be written. Default location: Determined by the following: "/opt/core.sh %p" (alternatively, falling back to testoutput/test-support/jtreg_open_test_jdk_tier1_part2/scratch/3/core.636346)
#
# If you would like to submit a bug report, please visit:
# https://bugreport.java.com/bugreport/crash.jsp
#

--------------- S U M M A R Y ------------

Command Line: -Xmx768m -XX:MaxRAMPercentage=6.25 -Dtest.boot.jdk=jdk/25/37/bundles/linux-aarch64/jdk-25_linux-aarch64_bin.tar.gz/jdk-25 -Djava.io.tmpdir=testoutput/test-support/jtreg_open_test_jdk_tier1_part2/tmp -ea -esa --enable-preview -Djava.library.path=jdk-26-valhalla+1-196/linux-aarch64-debug.test/jdk/jtreg/native --patch-module=java.base=testoutput/test-support/jtreg_open_test_jdk_tier1_part2/patches/java.base -Djava.security.policy=file:./testoutput/test-support/jtreg_open_test_jdk_tier1_part2/jtreg.policy com.sun.javatest.regtest.agent.AgentServer -id 10 -logfile testoutput/test-support/jtreg_open_test_jdk_tier1_part2/jtData/agentServer.10.trace -allowSetSecurityManager -port 47651 -timeoutFactor 4.0

Host: , AArch64, 8 cores, 30G, Oracle Linux Server release 9.6
Time: Wed Dec 17 11:50:53 2025 UTC elapsed time: 452.380391 seconds (0d 0h 7m 32s)

--------------- T H R E A D ---------------

Current thread (0x0000ffff9821a9f0): JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=636363, stack(0x0000ffff537d8000,0x0000ffff539d6000) (2040K)]


Current CompileTask:
C2:452380 11298 4 java.util.HashMap$TreeNode::find (172 bytes)

Stack: [0x0000ffff537d8000,0x0000ffff539d6000], sp=0x0000ffff539d14e0, free space=2021k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x19c5da4] TypePtr::compute_flat_in_array_if_unknown(ciInstanceKlass*, bool, TypePtr::FlatInArray) const+0xc4 (type.cpp:3159)
V [libjvm.so+0x19cbe58] TypeInstPtr::as_klass_type(bool) const+0x88 (type.cpp:4892)
V [libjvm.so+0x14f7270] LoadNKlassNode::Value(PhaseGVN*) const+0xc (memnode.cpp:2796)
V [libjvm.so+0x16b8700] PhaseGVN::transform(Node*)+0x1e0 (phaseX.cpp:703)
V [libjvm.so+0x16813b8] Parse::optimize_cmp_with_klass(Node*)+0x2ac (parse2.cpp:2660)
V [libjvm.so+0x16833f4] Parse::do_acmp(BoolTest::mask, Node*, Node*)+0x134 (parse2.cpp:2147)
V [libjvm.so+0x168c964] Parse::do_one_bytecode()+0x2a64 (parse2.cpp:3481)
V [libjvm.so+0x1672df8] Parse::do_one_block()+0x318 (parse1.cpp:1704)
V [libjvm.so+0x16741cc] Parse::do_all_blocks()+0x13c (parse1.cpp:761)
V [libjvm.so+0x1677878] Parse::Parse(JVMState*, ciMethod*, float)+0xb14 (parse1.cpp:665)
V [libjvm.so+0x848c8c] ParseGenerator::generate(JVMState*)+0xec (callGenerator.cpp:99)
V [libjvm.so+0xbe29f4] Parse::do_call()+0xd08 (doCall.cpp:777)
V [libjvm.so+0x168a3c0] Parse::do_one_bytecode()+0x4c0 (parse2.cpp:3527)
V [libjvm.so+0x1672df8] Parse::do_one_block()+0x318 (parse1.cpp:1704)
V [libjvm.so+0x16741cc] Parse::do_all_blocks()+0x13c (parse1.cpp:761)
V [libjvm.so+0x1677878] Parse::Parse(JVMState*, ciMethod*, float)+0xb14 (parse1.cpp:665)
V [libjvm.so+0x848c8c] ParseGenerator::generate(JVMState*)+0xec (callGenerator.cpp:99)
V [libjvm.so+0xa3c7b8] Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x10d8 (compile.cpp:825)
V [libjvm.so+0x84583c] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x2d8 (c2compiler.cpp:149)
V [libjvm.so+0xa4ba6c] CompileBroker::invoke_compiler_on_method(CompileTask*)+0xb08 (compileBroker.cpp:2345)
V [libjvm.so+0xa4c998] CompileBroker::compiler_thread_loop()+0x638 (compileBroker.cpp:1989)
V [libjvm.so+0xfb2888] JavaThread::thread_main_inner()+0x108 (javaThread.cpp:777)
V [libjvm.so+0x198efbc] Thread::call_run()+0xac (thread.cpp:242)
V [libjvm.so+0x162305c] thread_native_entry(Thread*)+0x11c (os_linux.cpp:860)
C [libc.so.6+0x80b50] start_thread+0x300