dlopen - undefined behavior

a.cpp

#include <iostream>

extern "C" {
int 
OpenTracingMakeTracerFactory(const char* opentracing_version,
                             const void** error_category,
                             void** tracer_factory) {
	std::cout << "called\n";
	return 0;
}
}

error

main.cpp:36:22: runtime error: call to function (unknown) through pointer to incorrect function type 'int (*)(const char *, const void **, void **)'
(liba.so+0x980): note: (unknown) defined here
called

main.cpp

#include <dlfcn.h>
#include <iostream>
#include <exception>

extern "C" {
int __attribute((weak))
		OpenTracingMakeTracerFactory(const char* opentracing_version,
                                             const void** error_category,
                                             void** tracer_factory);
}  // extern "C"


void f(const char* shared_library) {
  dlerror();

  const auto handle = dlopen(shared_library, RTLD_NOW | RTLD_LOCAL);
  if (handle == nullptr) {
    std::cerr << dlerror() << '\n';
    std::terminate();
  }

  int (*make_tracer_factory)(const char*, const void**, void**) =
      reinterpret_cast<decltype(OpenTracingMakeTracerFactory)*>(
          dlsym(handle, "OpenTracingMakeTracerFactory"));

  if (make_tracer_factory == nullptr) {
    std::cerr << dlerror() << '\n';
    dlclose(handle);
    std::terminate();
  }

    const void* error_category = nullptr;
  void* tracer_factory = nullptr;
  const auto rcode = make_tracer_factory("1.0.0", &error_category,
                                         &tracer_factory);
  (void)rcode;
  dlclose(handle);
}

int main() {
  f("./liba.so");
  return 0;
}

Makefile

all: a.cpp main.cpp
	clang++-5.0 -std=c++11 -fsanitize=undefined -g -fno-omit-frame-pointer -fPIC -shared a.cpp -o liba.so
	clang++-5.0 -std=c++11 -fsanitize=undefined -g -fno-omit-frame-pointer main.cpp -ldl

clean:
	rm a.out liba.so