Re: [PATCH] Combine location with block using block_locations

[Robert Dewar <dewar at adacore dot com>]

On 9/13/2012 9:38 AM, Jakub Jelinek wrote:
> On Thu, Sep 13, 2012 at 09:33:20AM -0400, Robert Dewar wrote:
> > On 9/13/2012 8:00 AM, Richard Guenther wrote:
> >
> > > Because doing so would create code generation differences -g vs. -g0.
> >
> > Sometimes I wonder whether the insistence on -g not changing code
> > generation is warranted. In practice, gdb for me is so weak in handling
>
> It is.  IMHO the most important reason is not that somebody would build
> first with just -O2 and then later on to debug the code would build it again
> with -g -O2 and hope the code is the same, but by making sure -g vs. -g0
> doesn't change generate code we ensure -g doesn't pessimize the generated
> code, and really many people compile even production code with -g -O2
> or similar.  The debug info is then either stripped, or stripped into
> separate files/not shipped or only optionally shipped with the product.
>
> 	Jakub
Sure, it is obvious that you don't want -g to affect -O1 or -O2 code,
but I think if you have -Og (if and when we have that), it would not
be a bad thing for -g to affect that. I can even imagine that what
-Og means is -O1 if you don't have -g, and something good for
debugging if you do have -g.