* cgraph.h (varpool_node_hook, varpool_node_hook_list,
varpool_add_node_removal_hook, varpool_add_variable_insertion_hook,
varpool_remove_variable_insertion_hook): Declare.
* varpool.c (varpool_node_hook_list): New structure.
(first_varpool_node_removal_hook,
first_varpool_variable_insertion_hook): New variables.
(varpool_add_node_removal_hook, varpool_remove_node_removal_hook,
varpool_call_node_removal_hooks, varpool_add_variable_insertion_hook,
varpool_remove_variable_insertion_hook,
varpool_call_variable_insertion_hooks): New functions.
(varpool_remove_node): Use it.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@202367 138bc75d-0d04-0410-961f-82ee72b054a4