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<p>Hi,<br>
I still have the feeling that we're looking at several pieces --
but missing the full picture. We know that:</p>
<p>* this is a custom C++ library<br>
* there is a C header which exports some of the C++ symbols with
`extern "C"`<br>
* this C++ library seems to depend on the datachannel library<br>
</p>
<p>We haven't seen how the Java side does the calling.</p>
<p>It would be really helpful if there was a self-contained
repository somewhere we could look at to try and reproduce (and
better understand) this issue.</p>
<p>As for this code, `make_unique` creates a new RtcManager object
-- so maybe something is up with the constructor call -- but hard
to say what could be (the issue could also be completely
unrelated).</p>
<p>If you remove most of the code from `createRtcContext` and just
leave this</p>
<p>```<br>
rtcManager = std::make_unique<RtcManager>()<br>
```</p>
<p>Does it still crash there?<br>
</p>
<p>Maurizio<br>
</p>
<div class="moz-cite-prefix">On 08/04/2025 01:51, bai li wrote:<br>
</div>
<blockquote type="cite" cite="mid:CAFEHhdb4cQfVpLusOTxdbbmqvuc_EVQFCbu3aaV9=dUeMrGRUg@mail.gmail.com">
<div dir="ltr">
<div>The createRtcContext function is like this：</div>
<div>
<div style="background-color:rgb(30,31,34);color:rgb(188,190,196)">
<pre style="font-family:"JetBrains Mono",monospace;font-size:9.8pt"><span style="color:rgb(207,142,109)">void </span><span style="color:rgb(86,168,245)">createRtcContext</span>(<span style="color:rgb(207,142,109)">const char</span>* localId, <span style="color:rgb(207,142,109)">int </span>logLevel, <span style="color:rgb(181,182,227)">IceConfig</span>* iceConfig, <span style="color:rgb(181,182,227)">DataChannelConfig</span>* dataChannelConfig) {
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"1" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
<span style="color:rgb(207,142,109)">int </span>expected = <span style="color:rgb(42,172,184)">0</span>;
<span style="color:rgb(207,142,109)">bool </span>success = state.compare_exchange_strong(expected, <span style="color:rgb(42,172,184)">1</span>);
<span style="color:rgb(207,142,109)">if </span>(!success) <span style="color:rgb(207,142,109)">return</span>;
<span style="color:rgb(207,142,109)">if </span>(localId == <span style="color:rgb(207,142,109)">nullptr</span>) <span style="color:rgb(207,142,109)">return</span>;
<span style="color:rgb(207,142,109)">if </span>(iceConfig == <span style="color:rgb(207,142,109)">nullptr</span>) <span style="color:rgb(207,142,109)">return</span>;
<span style="color:rgb(207,142,109)">if </span>(dataChannelConfig == <span style="color:rgb(207,142,109)">nullptr</span>) <span style="color:rgb(207,142,109)">return</span>;
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
<span style="color:rgb(181,182,227)">std</span>::<span style="color:rgb(185,188,209)">string </span>id = <span style="color:rgb(181,182,227)">std</span>::string(localId);
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2 1" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">" " </span><span style="color:rgb(95,140,138)"><< </span>id <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
<span style="color:rgb(181,182,227)">std</span>::make_unique<<span style="color:rgb(207,142,109)">int</span>>(<span style="color:rgb(42,172,184)">3</span>);
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2 1 1" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
rtcManager <span style="color:rgb(95,140,138)">= </span><span style="color:rgb(181,182,227)">std</span>::make_unique<<span style="color:rgb(181,182,227)">RtcManager</span>>(); <span style="color:rgb(122,126,133)">// Crash here!
</span><span style="color:rgb(122,126,133)"> </span><span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2 1 2" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
rtcManager<span style="color:rgb(95,140,138)">-></span>setLocalId(id);
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2 2" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
rtcManager<span style="color:rgb(95,140,138)">-></span>initLogger(logLevel);
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2 3" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
<span style="color:rgb(181,182,227)">IceModel </span>iceModel;
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2 4" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
iceModel.setNoStun(iceConfig-><span style="color:rgb(147,115,165)">noStun</span>);
iceModel.setStunServer(<span style="color:rgb(181,182,227)">std</span>::string(iceConfig-><span style="color:rgb(147,115,165)">stunServer</span>));
iceModel.setStunPort(iceConfig-><span style="color:rgb(147,115,165)">stunPort</span>);
iceModel.setUdpMux(iceConfig-><span style="color:rgb(147,115,165)">udpMux</span>);
iceModel.setWebSocketServer(<span style="color:rgb(181,182,227)">std</span>::string(iceConfig-><span style="color:rgb(147,115,165)">webSocketServer</span>));
iceModel.setWebSocketPort(iceConfig-><span style="color:rgb(147,115,165)">webSocketPort</span>);
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2 5" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
<span style="color:rgb(207,142,109)">auto </span>dataChannelListener = <span style="color:rgb(181,182,227)">DataChannelListener</span>::Builder()
.withOnOpen(dataChannelConfig-><span style="color:rgb(147,115,165)">onOpen</span>)
.withOnClosed(dataChannelConfig-><span style="color:rgb(147,115,165)">onClosed</span>)
.withOnTextMessage(dataChannelConfig-><span style="color:rgb(147,115,165)">onTextMessage</span>)
.withOnBinaryMessage(dataChannelConfig-><span style="color:rgb(147,115,165)">onBinaryMessage</span>)
.build();
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"2 6" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
<span style="color:rgb(181,182,227)">std</span>::<span style="color:rgb(181,182,227)">shared_ptr</span><<span style="color:rgb(181,182,227)">DataChannelListener</span>> dcListener = <span style="color:rgb(181,182,227)">std</span>::move(dataChannelListener);
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"3" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
rtcManager<span style="color:rgb(95,140,138)">-></span>initDataChannelListener(dcListener);
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"4" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
<span style="color:rgb(181,182,227)">std</span>::<span style="color:rgb(181,182,227)">unique_ptr</span><<span style="color:rgb(181,182,227)">WebSocketHelper</span>> webSocketHelper = rtcManager<span style="color:rgb(95,140,138)">-></span>connectToSignalingServer(iceModel);
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"5" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
<span style="color:rgb(207,142,109)">while </span>(state.load() == <span style="color:rgb(42,172,184)">1</span>) {
<span style="color:rgb(181,182,227)">std</span>::<span style="color:rgb(181,182,227)">this_thread</span>::yield();
}
<span style="color:rgb(181,182,227)">std</span>::cout <span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(106,171,115)">"6" </span><span style="color:rgb(95,140,138)"><< </span><span style="color:rgb(181,182,227)">std</span>::endl;
}</pre>
</div>
</div>
</div>
<br>
<div class="gmail_quote gmail_quote_container">
<div dir="ltr" class="gmail_attr">On Mon, Mar 31, 2025 at
5:26 PM bai li <<a href="mailto:k3315368931@gmail.com" moz-do-not-send="true" class="moz-txt-link-freetext">k3315368931@gmail.com</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr">Hi Panama team,<br>
<br>
I’m using the Java FFM API in JDK 21 to call a C++ dynamic
library function, `void createRtcContext(const char*
localId, int logLevel, IceConfig* iceConfig,
DataChannelConfig* dataChannelConfig)`. The function can be
invoked, but it crashes when executing
`std::make_unique<RtcManager>()` inside the function.
The same C++ code runs without any issues when executed
independently. The `RtcManager` class is roughly defined as
follows:<br>
<br>
```cpp<br>
class RtcManager {<br>
private:<br>
std::string localId;<br>
rtc::Configuration config;<br>
std::unordered_map<std::string,
std::shared_ptr<rtc::PeerConnection>>
peerConnectionMap;<br>
std::unordered_map<std::string,
std::shared_ptr<rtc::DataChannel>> dataChannelMap;<br>
std::shared_ptr<rtc::WebSocket> ws =
std::make_shared<rtc::WebSocket>();<br>
std::shared_ptr<DataChannelListener>
dataChannelListener = nullptr;<br>
public:<br>
explicit RtcManager(const std::string& id) :
localId(id) {}<br>
};
<div>
<div>The C++ code is compiled with MSVC 2022. Here’s the
crash log from the console:</div>
</div>
<div># A fatal error has been detected by the Java Runtime
Environment:<br>
#<br>
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at
pc=0x00007ffb0ca62f58, pid=22096, tid=26348<br>
#<br>
# JRE version: Java(TM) SE Runtime Environment (21.0.6+8)
(build 21.0.6+8-LTS-188)<br>
# Java VM: Java HotSpot(TM) 64-Bit Server VM
(21.0.6+8-LTS-188, mixed mode, sharing, tiered, compressed
oops, compressed class ptrs, g1 gc, windows-amd64)<br>
# Problematic frame:<br>
# C [msvcp140.dll+0x12f58]<br>
#<br>
# No core dump will be written. Minidumps are not enabled
by default on client versions of Windows<br>
#<br>
# An error report file with more information is saved as:<br>
# E:\projects\backend-projects\test\hs_err_pid22096.log<br>
[0.236s][warning][os] Loading hsdis library failed<br>
#<br>
# If you would like to submit a bug report, please visit:<br>
# <a href="https://bugreport.java.com/bugreport/crash.jsp" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">https://bugreport.java.com/bugreport/crash.jsp</a><br>
# The crash happened outside the Java Virtual Machine in
native code.<br>
# See problematic frame for where to report the bug.<br>
#<br>
</div>
<div>
<div>Thanks</div>
</div>
</div>
</blockquote>
</div>
</blockquote>
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