alternatives to "noalias"?

[Thomas M. Breuel]

Many optimizations that are possible because the compiler can assume
that two different names don't refer to the same location can be
expressed portably introducing explicit temporaries. Vectorization and
parallelization requires a declaration (or separate looping construct)
that states to the compiler that there are no (or "harmless")
sequential dependencies in a loop body.

What I would like to ask: ignoring programming style, can you think of
any optimizations that a FORTRAN compiler can carry out that cannot be
expressed portably using temporaries and one or two compiler
directives declaring absence of sequential dependencies in a loop
body?