Option ordering

[Manuel López-Ibáñez]

On 31/05/07, Jakub Jelinek <jakub@redhat.com> wrote:
> On Wed, May 30, 2007 at 09:23:34PM -0400, Diego Novillo wrote:
> > On 5/30/07 7:07 PM, Joe Buck wrote:
> >
> > > How about: have -Wall still set warn_strict_overflow
> > > to 1, but to have -Wall -Wstrict-overflow *or* -Wstrict-overflow -Wall
> > > *or* just -Wstrict-overflow set it to 2?  The only change would be
> > > to prevent -Wall from *decreasing* the value.
> >
> > Yes.  My idea was along similar lines.  Given an umbrella option like
> > -Wall or -Ox, it should only set specific options iff those options are
> > not present in the command line.
> >
> > That means that we have to have presence bits for each option.
>
> Or evaluate first the group options (-W{,no}-all, -Wextra, -O{,0,1,2,3,s})
> and then all other options.
>

That was what I was planning to do. We would also need to keep a
default value somewhere. Currently we initialise variables with
default values and we assign that value to -1 if we want to detect
uninitialisated variables. My proposal would be:

* Init all values to -1
* Handle command-line options into flags. Group options have their own
flag and don't touch the others.
* Handle group options: if the simple variable is still -1, then
assign the value of the group option.
* If the variable is still -1, assign the default value that
corresponds to the Init(value) in *.opt files. A missing Init(value)
would be assumed to mean Init(0).

Cheers,

Manuel