On Sat, Jun 13, 2009 at 08:00:35PM +0200, Eric Botcazou wrote:
> > Yes, I don't like -O0 producing worse debug info - what does
> > the -O0 -fvar-tracking-assignments results look like?
>
> I'd do the opposite: totally disable VTA at -O0 like we do for -fvar-tracking.
> We once tried to enable -fvar-tracking with -O0 at AdaCore and ended up with
> bloated and inferior debug info. I think we shouldn't need to do anything
> at -O0 apart from sufficiently curbing the code generator to get correct
> naive debug info; the sophisticated stuff should be reserved to -O and above.
I really think we need to do (limited) -fvar-tracking even for -O0, it is
really bad that most arguments have wrong locations through the prologue,
while at -O1 or above they often have correct location.
We should just do the tracking inside of the prologue or for register
variables, those that are stored into memory during the prologue and live in
memory shouldn't be tracked outside of the prologue at -O0.
Jakub
