[Bug tree-optimization/21998] (cond ? result1 : result2) is vectorized, where equivalent if-syntax isn't (store)

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21998

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> 2013-03-27 11:32:19 UTC ---
Note that the concern is also that a1 may be mapped to a read-only segment,
so introducing a store data-race may trap.  That's probably out of the C99
language standards scope, but the middle-end has to care about this
possibility.