The attached Java Fuzzer test starts to fail after JDK-8344035:
$ java -XX:CompileCommand=compileonly,*Test*::* -Xcomp Test.java
$ java -XX:CompileCommand=compileonly,*Reduced*::* -Xcomp Reduced.java
#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (c:\sb\prod\1738051592\workspace\open\src\hotspot\share\opto\loopnode.cpp:6501), pid=58544, tid=80648
# assert(false) failed: Bad graph detected in build_loop_late
#
# JRE version: Java(TM) SE Runtime Environment (25.0) (fastdebug build 25-internal-LTS-2025-01-28-0758193.axel.boldt-christmas.zgc)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 25-internal-LTS-2025-01-28-0758193.axel.boldt-christmas.zgc, compiled mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, windows-amd64)
# Problematic frame:
# V [jvm.dll+0xbc4be8] PhaseIdealLoop::build_loop_late_post_work+0x918
............
Command Line: -Xmx1G -XX:+IgnoreUnrecognizedVMOptions -XX:CompileCommand=quiet -XX:CompileCommand=compileonly,*Test*::* -Xcomp -XX:MaxRAMPercentage=4.16667 -Dtest.boot.jdk=c:\ade\mesos\work_dir\jib-master\install\jdk\23\37\bundles\windows-x64\jdk-23_windows-x64_bin.zip\jdk-23 -Djava.io.tmpdir=c:\sb\prod\1738074992\testoutput\test-support\jtreg_closed_test_hotspot_jtreg_applications_javafuzzer_BigTest_java\tmp -XX:+CreateCoredumpOnCrash Test
...........
C2:2514 48 !b 4 Test::mainTest (680 bytes)
Stack: [0x000000bad7200000,0x000000bad7300000], sp=0x000000bad72fba00, free space=1006k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [jvm.dll+0xbc4be8] PhaseIdealLoop::build_loop_late_post_work+0x918 (loopnode.cpp:6501)
V [jvm.dll+0xbc4134] PhaseIdealLoop::build_loop_late+0x314 (loopnode.cpp:6314)
V [jvm.dll+0xbc298c] PhaseIdealLoop::build_and_optimize+0x88c (loopnode.cpp:4779)
V [jvm.dll+0x558fcc] Compile::Optimize+0xb6c (compile.cpp:2429)
V [jvm.dll+0x556183] Compile::Compile+0x11a3 (compile.cpp:852)
V [jvm.dll+0x45d059] C2Compiler::compile_method+0x179 (c2compiler.cpp:144)
V [jvm.dll+0x5741ca] CompileBroker::invoke_compiler_on_method+0x7aa (compileBroker.cpp:2318)
V [jvm.dll+0x5717cb] CompileBroker::compiler_thread_loop+0x33b (compileBroker.cpp:1977)
V [jvm.dll+0x8baa12] JavaThread::thread_main_inner+0x282 (javaThread.cpp:777)
V [jvm.dll+0xfa7144] Thread::call_run+0x1b4 (thread.cpp:236)
V [jvm.dll+0xd6a261] thread_native_entry+0xe1 (os_windows.cpp:566)
C [ucrtbase.dll+0x26b4c] (no source info available)
C [KERNEL32.DLL+0x14cb0] (no source info available)
C [ntdll.dll+0x7ecdb] (no source info available)