https://mail.openjdk.org/pipermail/leyden-dev/2025-April/001905.html

I tested the premain branch on a pretty large Spring Boot application (>1M
loc, fat jar is about 240MB):

I had a segfault on application start.
I tracked down the issue to:
- use the Bouncy Castle security provider
- run as a Spring Boot app.

I created a reproducer there https://github.com/obourgain/leyden-crash
I couldn't reproduce as a simple main, but it should be possible to reduce
the size of the reproducer even more.

Some observations:

- During the aotconf creation, bouncy castle classes are excluded
because they are from a signed jar like:
Skipping org/bouncycastle/jcajce/provider/asymmetric/util/BaseKeyFactorySpi: Signed JAR

- During the AOT cache creation there are a lot of warnings , it may be related to the crash:
[1,064s][warning][cds,heap] Archive heap points to a static field that
may hold a different value at runtime:
[1,064s][warning][cds,heap] Field: sun/security/x509/AlgorithmId::SHA3_512withRSA_oid
[1,064s][warning][cds,heap] Value: sun.security.util.ObjectIdentifier
[1,064s][warning][cds,heap] {0x00000006000453b8} - klass: 'sun/security/util/ObjectIdentifier' - flags:
[1,064s][warning][cds,heap]
[1,064s][warning][cds,heap] - ---- fields (total size 4 words):
[1,064s][warning][cds,heap] - private 'componentLen' 'I' @12 -1 (0xffffffff)
[1,064s][warning][cds,heap] - private transient 'componentsCalculated' 'Z' @16 false (0x00)
[1,064s][warning][cds,heap] - private 'encoding' '[B' @20 [B{0x00000006000453d8} (0xc0008a7b)
[1,064s][warning][cds,heap] - private volatile transient 'stringForm' 'Ljava/lang/String;' @24 "2.16.840.1.101.3.4.3.16"{0x0000000600045378} (0xc0008a6f)
[1,064s][warning][cds,heap] - private 'components' 'Ljava/lang/Object;' @28 null (0x00000000)
[1,064s][warning][cds,heap] --- trace begin ---
[1,064s][warning][cds,heap] [ 0] {0x0000000600043330} java.util.concurrent.ConcurrentHashMap::table (offset = 20)
[1,064s][warning][cds,heap] [ 1] {0x0000000600043370} [Ljava.util.concurrent.ConcurrentHashMap$Node; @[87]
[1,064s][warning][cds,heap] [ 2] {0x0000000600045358} java.util.concurrent.ConcurrentHashMap$Node::val (offset = 20)
[1,064s][warning][cds,heap] [ 3] {0x00000006000453b8} sun.security.util.ObjectIdentifier
[1,064s][warning][cds,heap] --- trace end ---

- Sample Backtrace from the segfault:
💣 Program crashed: Bad pointer dereference at 0x0000000000000000

Thread 2 crashed:

 0 0x0000000000000000
 1 0x00000001132b5230
 2 0x00000001132b0154
 3 JavaCalls::call_helper(JavaValue*, methodHandle const&,
JavaCallArguments*, JavaThread*) + 988 in libjvm.dylib at
make/hotspot/src/hotspot/share/runtime/javaCalls.cpp:415:7
 4 InstanceKlass::call_class_initializer(JavaThread*) + 764 in libjvm.dylib at make/hotspot/src/hotspot/share/oops/instanceKlass.cpp:1777:5
 5 InstanceKlass::initialize_impl(JavaThread*) + 2748 in libjvm.dylib at make/hotspot/src/hotspot/share/oops/instanceKlass.cpp:1331:7
6 InstanceKlass::initialize_impl(JavaThread*) + 1540 in libjvm.dylib at make/hotspot/src/hotspot/share/oops/instanceKlass.cpp:1292:20
 7 HeapShared::resolve_or_init_classes_for_subgraph_of(Klass*, bool, JavaThread*) + 900 in libjvm.dylib at make/hotspot/src/hotspot/share/cds/heapShared.cpp:1491:9
 8 HeapShared::initialize_from_archived_subgraph(JavaThread*, Klass*) + 336 in libjvm.dylib at make/hotspot/src/hotspot/share/cds/heapShared.cpp:1415:5
 9 JVM_InitializeFromArchive + 560 in libjvm.dylib at make/hotspot/src/hotspot/share/prims/jvm.cpp:3369:3
10 0x00000001132b8e80
11 0x00000001132b4a90
12 0x00000001132b0154
13 JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, JavaThread*) + 988 in libjvm.dylib at make/hotspot/src/hotspot/share/runtime/javaCalls.cpp:415:7
14 InstanceKlass::call_class_initializer(JavaThread*) + 764 in libjvm.dylib at make/hotspot/src/hotspot/share/oops/instanceKlass.cpp:1777:5
15 InstanceKlass::initialize_impl(JavaThread*) + 2748 in libjvm.dylib at make/hotspot/src/hotspot/share/oops/instanceKlass.cpp:1331:7
16 LinkResolver::resolve_static_call(CallInfo&, LinkInfo const&, bool, JavaThread*) + 152 in libjvm.dylib at make/hotspot/src/hotspot/share/interpreter/linkResolver.cpp:1116:21
17 LinkResolver::resolve_invokestatic(CallInfo&, constantPoolHandle const&, int, JavaThread*) + 52 in libjvm.dylib at make/hotspot/src/hotspot/share/interpreter/linkResolver.cpp:1749:3
18 LinkResolver::resolve_invoke(CallInfo&, Handle, constantPoolHandle const&, int, Bytecodes::Code, JavaThread*) + 116 in libjvm.dylib at make/hotspot/src/hotspot/share/interpreter/linkResolver.cpp:1708:39
19 InterpreterRuntime::resolve_invoke(JavaThread*, Bytecodes::Code) + 748 in libjvm.dylib at make/hotspot/src/hotspot/share/interpreter/interpreterRuntime.cpp:988:5
20 InterpreterRuntime::resolve_invokestatic(JavaThread*) + 420 in libjvm.dylib at make/hotspot/src/hotspot/share/interpreter/interpreterRuntime.cpp:952:3
21 InterpreterRuntime::resolve_from_cache(JavaThread*, Bytecodes::Code) + 2644 in libjvm.dylib at make/hotspot/src/hotspot/share/interpreter/interpreterRuntime.cpp:1167:37
22 0x00000001132c48c4
23 0x00000001132b0154
24 JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, JavaThread*) + 988 in libjvm.dylib at make/hotspot/src/hotspot/share/runtime/javaCalls.cpp:415:7
25 InstanceKlass::call_class_initializer(JavaThread*) + 764 in libjvm.dylib at make/hotspot/src/hotspot/share/oops/instanceKlass.cpp:1777:5
26 InstanceKlass::initialize_impl(JavaThread*) + 2748 in libjvm.dylib at make/hotspot/src/hotspot/share/oops/instanceKlass.cpp:1331:7
27 InstanceKlass::initialize_impl(JavaThread*) + 1540 in libjvm.dylib at make/hotspot/src/hotspot/share/oops/instanceKlass.cpp:1292:20
28 HeapShared::init_classes_for_special_subgraph(Handle, JavaThread*) + 356 in libjvm.dylib at make/hotspot/src/hotspot/share/cds/heapShared.cpp:1387:13
29 Threads::create_vm(JavaVMInitArgs*, bool*) + 1504 in libjvm.dylib at make/hotspot/src/hotspot/share/runtime/threads.cpp:808:5
30 JNI_CreateJavaVM_inner(JavaVM_**, void**, void*) + 80 in libjvm.dylib at make/hotspot/src/hotspot/share/prims/jni.cpp:3587:12
31 JNI_CreateJavaVM + 116 in libjvm.dylib at make/hotspot/src/hotspot/share/prims/jni.cpp:3678:14
32 InitializeJVM + 184 in libjli.dylib at make/src/java.base/share/native/libjli/java.c:1510:9
33 JavaMain + 256 in libjli.dylib at make/src/java.base/share/native/libjli/java.c:494:10
34 ThreadJavaMain + 12 in libjli.dylib at make/src/java.base/macosx/native/libjli/java_md_macosx.m:679:29
35 0x0000000197d71c0c _pthread_start + 136 in libsystem_pthread.dylib

With regards to performance, with disabling the loading of
BouncyCastleProvider in the application, it starts way faster and with
lower resources, impressive work.

- baseline (extracted Spring Boot jar)
  Time (mean ± σ): 11.510 s ± 0.432 s [User: 32.354 s, System:
1.751 s]

- Leyden main branch
  Time (mean ± σ): 6.031 s ± 0.090 s [User: 12.591 s, System:
0.513 s]
aotcache file = 250 MB

- Leyden premain branch
  Time (mean ± σ): 4.801 s ± 0.022 s [User: 6.662 s, System: 0.390
s]
aotcache file = 300 MB