How to find the cause of crash?

[zhmt via Digitalmars-d-learn]

On Wednesday, 11 March 2015 at 10:13:12 UTC, Théo Bueno wrote:
> On Wednesday, 11 March 2015 at 08:16:17 UTC, zhmt wrote:
>> Now , my question is:
>> How to get the position it crashes?
>> Or get the method call stack?
>
> If you are developing under Linux, you can use GDB to debug 
> your D apps, just like any C/C++ program. Make sure you are 
> compiling in debug mode in order to have debug symbols in your 
> binary.
>
> Under Windows, there is Mago with VisualD.
>
> Please refer to this page for more details on available 
> debuggers : http://wiki.dlang.org/Debuggers
>
> If you don't know how to use these debuggers, there is a lot of 
> documentation available on the web :)


Thank you very much.
I got the call stack by gdb:

Program received signal SIGSEGV, Segmentation fault.
0x000000000077ca11 in 
vibe.core.drivers.libevent2_tcp.onSocketEvent (
     buf_event=0xcd43f8, status=17, arg=0xcd54e0)
     at 
../../../../root/.dub/packages/vibe-d-0.7.22/source/vibe/core/drivers/libevent2_tcp.d:651

Here is the code of libevent2_tcp.d:

if (ctx.writeOwner && ctx.writeOwner != ctx.readOwner && 
ctx.writeOwner.running) {
				logTrace("resuming corresponding task%s...", ex is null ? "" 
: " with exception");
				if (ctx.writeOwner.fiber.state == Fiber.State.EXEC) 
ctx.exception = ex;
				else ctx.core.resumeTask(ctx.writeOwner, ex);   //LINE 651
			}


I dont know what is happening, may I should get help from vibe.d 
forum.