Initialize global.statics_read in ipa-reference

[Jan Hubicka]

Hi,
while working on allocator reorg for summaries I noticed that
we never initialize statics_read in ipa-reference which is later used to
bookkeep the strongly connected components.  I am bit surprised that
this ever worked w/o crashing, but it seems to be the case.

Bootstrapped/regteted x86_64-linux, comitted.

Index: ipa-reference.c
===================================================================
--- ipa-reference.c     (revision 277780)
+++ ipa-reference.c     (working copy)
@@ -492,6 +493,7 @@ init_function_info (struct cgraph_node *
 
   info->local.statics_read = BITMAP_ALLOC (&local_info_obstack);
   info->local.statics_written = BITMAP_ALLOC (&local_info_obstack);
+  info->global.statics_read = NULL;
 
   return &info->local;
 }