dlopen() not initializing modules?

[Charles Y. Kim]

So does anyone know if there's a magic linker flag to initialize static
globals in shared objects using GCC3.0.4 under HP-UX11?

Take the following super simple case:

	class myClass {
	public:
		int x;
		myClass() {
			x = 5;
		}
	};

	myClass test;

	extern "C" void run()
	{
		cout << test.x << endl;
	}

I dlopen() the file that contains this code, use dlsym to get a pointer to
run(), and then run the function.  The myClass constructor is never run so
when I print out test.x I get 0 instead of 5!

How do I fix this?

Thanks.

- Charles

 -----Original Message-----
From: 	Charles Y. Kim [mailto:ckim@telcontar.com]
Sent:	Monday, June 03, 2002 10:32 AM
To:	'gcc-help@gcc.gnu.org'
Subject:	dlopen() not initializing modules?

Hi all,

When I dlopen() a shared object, it looks like the module initializations
aren't being performed and the constructors for globals aren't getting
called (I verified this with a small test program).

Does anyone know how I might fix this?

Here's my test code:
#include <map>
#include <string>
#include <stdio.h>
#include <iostream.h>

class myMap {
public:
  void add(int x, int y) {
    m[x] = y;
  }
  myMap() {
    puts("Constructor run");
  }
private:
  std::map<int, int> m;
};

//myMap m2;

extern "C" int run() {
  myMap m2;
  m2.add(1, 2);
}

This shared object is being opened like this:
int main() {
  void *handle;
  void (*function)();
  handle = dlopen("./maptest.so", RTLD_LAZY);
  char *err;
  err = dlerror();
  if(err != NULL)
    cout << "File Load failure: " << err << endl;
  function = (void(*)())dlsym(handle, "run");
  err = dlerror();
  if(err != NULL)
    cout << "Load failure: " << err << endl;
  else {
    for (int i = 0; i < 1000000000; i++) {
      cout << "Count: " << i << endl;
      function();
    }
  }
}

I'm dlopen()ing this file built as a shared object.  When I declare a myMap
in global, the constructor is never run, and I end up with a segmentation
fault/core dump.

Anyone have any ideas?  I'm running GCC3.0.4 on HP-UX11i.

Thank in advance.

- Charles