Files illustrating simple attempt at making a D shared library with GDC.

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);
}

main.d

import std.stdio;
import std.c.linux.linux;
import std.string;

extern (C) void perror(char* s);
extern (C) void exit(int status);
extern (C) char* dlerror();

void main()
{
   void* handle = dlopen("./libtest.so\0".ptr, RTLD_LAZY);
   if (handle == null) {
     printf("%s\n", dlerror());
     exit(1);
   }
   void function() hiD = cast(void function()) dlsym(handle, ("hiD").ptr);
   if (hiD != null) {
     hiD();
   }
   else { writeln("hiD is null"); }
   dlclose(handle);
}

test.c

#include <stdio.h>

void hiD() {
	printf("hi from c\n");
}

test.d

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

I've tried this several ways. Currently, I'm trying to dlopen() the D version of libtest.so from the C version of main:

gdc -c test.d -fPIC
gdc -o libtest.so -shared test.o
gcc main.c
./a.out

I receive the following error:
cannot allocate memory in static TLS block