On test compiler/valhalla/inlinetypes/TestValueConstruction.java#StressIncrementalInliningOnStackReplacement with flags

-XX:+UnlockDiagnosticVMOptions -XX:+SafepointALot -XX:+DeoptimizeALot -XX:+DeoptimizeNMethodBarriersALot -XX:MaxNodeLimit=100000

one can get

#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (.../src/hotspot/share/opto/callGenerator.cpp:839), pid=3094568, tid=3094588
# assert(buffer_oop == nullptr) failed: unused buffer allocation
#
# JRE version: Java(TM) SE Runtime Environment (27.0+1) (fastdebug build 27-valhalla+1-140)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 27-valhalla+1-140, mixed mode, sharing, compressed oops, compressed class ptrs, g1 gc, linux-aarch64)
# Problematic frame:
# V [libjvm.so+0x850b58] CallGenerator::do_late_inline_helper()+0x16f8
#

with backtrace:


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

Current thread (0x0000ffff901c8930): JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=3094588, stack(0x0000ffff80219000,0x0000ffff80417000) (2040K)]


Current CompileTask:
C2:16993 868 b compiler.valhalla.inlinetypes.TestValueConstruction::run (1047 bytes)

Stack: [0x0000ffff80219000,0x0000ffff80417000], sp=0x0000ffff80411710, free space=2017k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x850b58] CallGenerator::do_late_inline_helper()+0x16f8 (callGenerator.cpp:839)
V [libjvm.so+0xa4151c] Compile::inline_incrementally_one()+0x19c (compile.cpp:2678)
V [libjvm.so+0xa42588] Compile::inline_incrementally(PhaseIterGVN&)+0x2c8 (compile.cpp:2771)
V [libjvm.so+0xa446b4] Compile::Optimize()+0x368 (compile.cpp:2909)
V [libjvm.so+0xa47278] Compile::Compile(ciEnv*, ciMethod*, int, Options, DirectiveSet*)+0x14c8 (compile.cpp:886)
V [libjvm.so+0x847d14] C2Compiler::compile_method(ciEnv*, ciMethod*, int, bool, DirectiveSet*)+0x2f0 (c2compiler.cpp:150)
V [libjvm.so+0xa561cc] CompileBroker::invoke_compiler_on_method(CompileTask*)+0xb08 (compileBroker.cpp:2345)
V [libjvm.so+0xa570f8] CompileBroker::compiler_thread_loop()+0x638 (compileBroker.cpp:1989)
V [libjvm.so+0xfc3d48] JavaThread::thread_main_inner()+0x108 (javaThread.cpp:777)
V [libjvm.so+0x19adccc] Thread::call_run()+0xac (thread.cpp:243)
V [libjvm.so+0x163e50c] thread_native_entry(Thread*)+0x11c (os_linux.cpp:929)
C [libc.so.6+0x80b50] start_thread+0x300