>  Should weak hidden undefined symbol be allowed? The problem is when
>  compiler sees a hidden symbol, it assumes
>  that it will be defined in the same component and optimizes its
>  access. If the hidden symbol is weak and undefined,
>  our linker won't report the error since the undefined symbol weak is
>  allowed.  Although its value is 0,  it may be
>  impossible to make its address to 0 in a shared library since the load
>  address of a shared library isn't known at
>  link-time.