Why does object creation give segmentation fault in DLL?

[Tolga Cakiroglu]

On Saturday, 22 February 2014 at 11:08:41 UTC, evilrat wrote:
> On Saturday, 22 February 2014 at 09:09:42 UTC, Tolga Cakiroglu 
> wrote:
>> I have written a DLL file in Linux (x86_64). It is as below:
>>
>> File: lib.dll
>> =====================
>> class A{}
>>
>> extern(C) void foo(){
>> 	Object obj = new Object();   // test 1
>>
>> 	A objA = new A();  // test 2
>>
>> 	char[] c = new char[ 1024 ];   // test 3
>> }
>>
>>
>> Compilation code is below:
>> 	dmd -c lib.d -fPIC -debug
>> 	gcc --shared lib.o -o lib.so
>>
>>
>> Output of programme is like that:
>> library is loaded now
>> foo() function is found
>> unloading libdll.so
>> Segmentation fault (core dumped)
>>
>>
>> Situation is that if either only the `test 1` or `test 3` code 
>> is available in the function, there is no error at all. But 
>> once I use `test 2` code, it starts giving segmentation fault. 
>> Please notice that both `test 1` and `test 2` are creating an 
>> object already. And all of them allocates memory with `new` 
>> keyword. But only the `test 2` fails. Why is this happening?
>
> you should init runtime in library and set gc proxy for it(if 
> implemented on linux, otherwise you would have two gc's running 
> simultaneously)
>
> so add following methods to your lib.
>
>
> // lib side
> void initRT()
> {
> import core.runtime();
> Runtime.initilize();
> }
>
> extern(C) void  gc_setProxy(void* p);
> void setGCProxy(void* gc)
> {
> gc_setProxy(gc);
> }
>
> // executable side
>
> extern(C) void* gc_getProxy();
>
> void main()
> {
> // load lib here
> initRT();
> setGCProxy(gc_getProxy());
> // do stuff here...
> }

After doing these, even without `test 2` segmentation fault 
started coming. I actually do not want to share GC between them 
right now.