Shared library in D on Linux

[Timo Westkämper" <timo.westkamper at gmail.com>]

I am still testing which setup gives me reliable shared D 
libraries which can be used from C.

Here is my latest test:

* test.d:
import std.stdio;
extern (C) {
   void hiD() {
     writeln("hi from D lib");
   }
}

* main.c
#include <stdio.h>
#include <dlfcn.h>
#include <stdlib.h>
void main() {
     void (*hiD)(void);
     void* handle = dlopen("./libtest.so", RTLD_LAZY);
     if (handle == NULL) {
         printf("%s\n", dlerror());
         exit(1);
     }	
     hiD = dlsym(handle, "hiD");
     if (hiD != NULL) {
         hiD();
     } else {
         printf("hiD is null\n");
     }
     dlclose(handle);
}

* Makefile
#!/bin/bash
test:
	#gdc-4.6 -g -c test.d -fPIC -o test.o
	#gdc-4.6 -shared -o libtest.so -fPIC test.o -lc -nostartfiles
	dmd -g -c test.d -fPIC
	ld -shared -o libtest.so test.o -lrt -lphobos2 -lpthread
	gcc -g main.c -ldl -lpthread
	./a.out
clean:
	rm -rf *.so *.o *.out

With this setup I get

   ./libtest.so: undefined symbol: _deh_beg

With a fake main method added I get

   make: *** [test] Segmentation fault

This is what I get from gdb

   Program received signal SIGSEGV, Segmentation fault.
   0xb7fd1ed3 in std.stdio.__T7writelnTAyaZ.writeln() 
(_param_0=...) at   /usr/include/d/dmd/phobos/std/stdio.d:1550
   1550	    enforce(fprintf(.stdout.p.handle, "%.*s\n",

Event with the following startup hooks

extern(C) {

   void gc_init();
   void gc_term();

   void _init() {
     gc_init();
   }

   void _fini() {
     gc_term();
   }

}

I get the same error. I am using dmd 2.058 on Ubuntu 11.10 (32 
bit)

With gdc I get different errors, but it seems even more difficult 
to get it working.

Does anyone know what is missing to get proper shared library 
support working on Linux?