my_sys DYNAMIC_ARRAY and DYNAMIC_STRING inconsistancy

extern my_bool init_dynamic_string(DYNAMIC_STRING *str, const char *init_str,   

                                   size_t init_alloc,size_t alloc_increment);

extern my_bool init_dynamic_array2(PSI_memory_key psi_key, DYNAMIC_ARRAY *array,

                                   uint element_size, void *init_buffer,        

                                   uint init_alloc, uint alloc_increment,       

                                   myf my_flags);