Mono embeded : NullReferenceException for a lock on a non-null object

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Hi,

I am embedding mono in a qt application on Windows, and when executing
code, I have a SIGSEGV in managed code, that is a NullReferenceException,
but my variable is not null.

I am on Windows 10 x64.
I have installed Mono 5.0.1 (Visual Studio built mono) x86.
I code on Qt 5.3 with MinGW x86.

I have a native method that calls a managed method :
mono_runtime_invoke(method, obj, args, &exceptionObject).

In my managed method, I have a "lock" statement :
lock(this.myVar) { ... }

The SIGSEGV (or NullReferenceException) is raised only when the native
method is called on the second time. When called the first time, it works
well.
Between the two calls, nothing has changed.

What can be the source of the error ?

Thanks.

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<div dir=3D"ltr">Hi,<br><br>I am embedding mono in a qt application on Wind=
ows, and when executing code, I have a SIGSEGV in managed code, that is a N=
ullReferenceException, but my variable is not null.<br><br>I am on Windows =
10 x64.<br>I have installed Mono 5.0.1 (Visual Studio built mono) x86.<br>I=
 code on Qt 5.3 with MinGW x86.<br><br>I have a native method that calls a =
managed method :<br>mono_runtime_invoke(method, obj, args, &amp;exceptionOb=
ject).<div><br></div><div>In my managed method, I have a &quot;lock&quot; s=
tatement :</div><div>lock(this.myVar) { ... }<br></div><div><br></div><div>=
The SIGSEGV (or NullReferenceException) is raised only when the native meth=
od is called on the second time. When called the first time, it works well.=
</div><div>Between the two calls, nothing has changed. </div><div><br></div=
><div>What can be the source of the error ?</div><div><br></div><div>Thanks=
.</div></div>

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