Ada broken on i686-linux (some progress)

[Richard Kenner]

    It would be usefull to know the backtraces at least here.  The second
    problem looks like yet another tree node sharing problem, so in the
    case the failure is within tree-ssa-loop-ivopts, I will try to add
    more of unsave_exprs to uses that might result in sharing and lets see
    if it fix it.

I can confirm this is a loop issue because it doesn't happen when
I disable loop optimizations.

    What is the current situation of ada aware gdb?  I used to have one but
    it no longer works on 3.5 GCC produced dwarf and the default in my
    instalation just die horribly seeing ada.

I almost never used an Ada-aware GDB even in the few times I'm
debugging in the Ada part of the front end.  I am indeed having
problems finding a GDB that works well with 4.0-GCC-produced code, but
it does not seem related to Ada per se: it appears that it's just like
other issues where Ada produces more complex code that triggers latent
bugs either in debug output creation or reading.