Re: [RFC] Optimization Diary

[Andrew Pinski <pinskia at physics dot uc dot edu>]

On Jun 6, 2006, at 10:34 PM, Devang Patel wrote:

> Andrew Pinski wrote:
> > On Jun 6, 2006, at 9:49 PM, Devang Patel wrote:
> > > We can allocate space in numbering for vendor extensions.
> >
> > What happens when you compile two sources with two different  
> > compilers and they
> > use the same number for vendor extension?
>
> What happens when another compiler uses 0x4104 TAG value for
> something else and GCC uses it for DW_TAG_GNU_BINCL ?

Not my fault and not really related because we are creating a new  
standard and
don't want to repeat this mistake, messages don't have this issue.

> > You just end up with weird results
> > in the IDE or performance analysis program.
> > Also what happens after you fill up the vendor extension range?
> What happens when vendor extension range for TAGs and Attributes  
> are full ?

Who cares, we are trying making something which is useful and not  
making something which
is going to be limited.

> > Also what happens when you change your compiler but not IDE, but  
> > you don't
> > want to update the IDE?
> What happens when GCC adds new DWARF extension but you do not want
> to update GDB ?

Again, we are trying to make something useful and extendable. If you  
don't
care about usefulness and extendibility then go ahead and use numbers.

Having the message gets rid of having duplicated code in each program  
that processes
the numbers, you have the message right away without doing extra work.

You really should listen to Daniel Berlin if you ever want this to be  
officially
part of the dwarf2 standard.  Remember he is part of the committee  
there.

You get extendibility for free and no need to change the IDE every  
thing you want to
add a new diary entry.  What more do you want something for free or  
something which
limits the use?  If you want something which is limited you may as  
well then just not
use dwarf2 and instead write out a text file.

-- Pinski