looking for hint to debug a strange multi-thread bug (grpc-d-core)

[mw]

Hi,

I recently found and started playing with the grpc-d-core[1] 
package, and my program structure looks like this:

https://github.com/mw66/grpc-demo/blob/master/source/main.d

If I run L64 alone (without L66 ~ 79 grpc-d part):
```
64: auto t = new Thread({fun();}).start();
```
it works fine.

If I run L66 ~ 79 grpc-d part alone (without L64), it also works 
fine.

But if I run both, the program received signal SIGSEGV, 
Segmentation fault at here:

https://github.com/mw66/grpc-d/blob/master/source/grpc/server/package.d#L94

with LDC, the print out of `services.keys` shows its corrupted 
with some strange values.

under DMD, it fails at:

https://github.com/mw66/grpc-d/blob/master/source/grpc/server/package.d#L99

while the `services.keys` seems fine.

What puzzles me is that: these two parts of the code are actually 
independent, does not know each other at all (as I just started 
to add the grpc-d skeleton code with dummy returns, and no client 
connected or made any rpc calls).

And the `services` defined here is a private class field:

https://github.com/mw66/grpc-d/blob/master/source/grpc/server/package.d#L21

So how can it be corrupted by `fun()`?


Any suggestions where should I look into?

Thanks.


[1] https://code.dlang.org/packages/grpc-d-core