[LLVMdev] constantexpr problem

[Duncan Sands]

Hi Tsingray,

>     I have got a problem when I used the use_empty() member function while I
> used a global variable. I erase all the instructions which will use a global
> variable. Then I called the use_empty() on that global variable. I got no empty
> because a constantexpr use the global variable. I wonder whether there is any
> way to erase the constantexpr which is useless to me but occupying the global
> variable.

if G is your global variable, do
   G->replaceAllUsesWith(UndefValue::get(G->getType()));
to replace G with undef in all users of G.  You can then safely delete G.

Ciao, Duncan.