Should -fcross-jumping be part of -O1?

[Robert Dewar]

Richard Kenner wrote:

>     Well as part of this thought experiment, please consider that if each
>     of these five axes has three settings, then there are 3**5
>     combinations, which is a large number, and of course there is no
>     possibility of the compiler behaving in 3**5 significantly different ways.
> 
> Right now, I count about 20 different optimizations switches and
> 2**20 is significantly larger than 3**5!

That's not the right comparison. If you go this route, then you need a
manual that for each of the 243 combinations of optimziation swithces
tells you which of these 2**20 possibilities applies to that combination.

Sounds like a mess to me (actually I count more than 20 optimziation 
options :-)