[Bug tree-optimization/38564] [4.4 Regression] ICE in insert_into_preds_of_block

["pinskia at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #2 from pinskia at gcc dot gnu dot org  2008-12-18 02:09 -------
Reduced testcase:
struct list_head {
        struct list_head *next, *prev;
};
struct list_head *__current_thread_info;
void test_ti_thread_flag(void*);
 int __do_page_cache_readahead(  int nr_to_read    )
{
        struct list_head page_pool = { &(page_pool), &(page_pool) };
        int page_idx;
        for (page_idx = 0; page_idx < nr_to_read; page_idx++)
                 test_ti_thread_flag(__current_thread_info);
        return (page_pool.next == &page_pool);
}
--- CUT ---
I think this comes from PREing of comparisons.
Changing this to just return of page_pool.next  works.  now I want to say this
code should always return true as page_pool does not escape at all but I don't
think GCC's aliasing is smart enough anyways.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
  GCC build triplet|x86_64-unknown-linux-gnu    |
   GCC host triplet|x86_64-unknown-linux-gnu    |
 GCC target triplet|x86_64-unknown-linux-gnu    |
   Last reconfirmed|0000-00-00 00:00:00         |2008-12-18 02:09:04
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38564