Avoid having visibility attribute directly in the code by
adding a _GLIB_EXTERN-decorated declaration for the exported
variables.
void gplugin_say_boo_func (void);
void gplugin_a_module_func (GModule *module);
-__attribute__((visibility("default"))) gchar* gplugin_a_state;
+_GLIB_EXTERN gchar* gplugin_a_state;
+gchar* gplugin_a_state;
_GLIB_EXTERN void
gplugin_a_func (void)
#include <gmodule.h>
-__attribute__((visibility("default"))) gchar* gplugin_b_state;
+_GLIB_EXTERN gchar* gplugin_b_state;
+gchar* gplugin_b_state;
const gchar* g_module_check_init (GModule *module);
void g_module_unload (GModule *module);