------- Comment #12 from manu at gcc dot gnu dot org  2008-08-19 02:33 -------
The key difference is -ftree-vrp (which is enabled at -O2). With INIT=2, it is
missing the obvious optimization that it detects with INIT=1. I wonder if this
is expected (after all, it is value-RANGE-propagation) or there is a PR open
about this.

Notice that any two consecutive integers trigger the optimization 0,1 but also
1,2 and thus remove the bogus uninitialized warning.


-- 

manu at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|bogus uninitialized warning |bogus uninitialized warning
                   |(loop representation)       |(loop representation, VRP
                   |                            |missed-optimization)


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36296

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