Re: [22.1.90]: Point before start of properties

[Stefan Monnier <monnier@iro.umontreal.ca>]

> I can reproduce it (ie, it breaks on the call to error as above) with
> lucid and motif scrollbars (tried with gcc-4.1.2)
> I can reproduce it with gcc-4.1.2 (-g and -g -O2) and gcc-4.2.3 (-g -O
> and -g -O2).
> I cannot reproduce it with gcc-4.2.3 (-g) and CC-5.7 (-g).

So, adding -O (or -O2) to gcc-4.2.3 triggers the problem, and switching
to gcc-4.1.2 triggers it as well?

It does sound like it may be a compiler bug, but [putting on my
compiler writer hat] it's still at least as likely that the bug is in
our code and just isn't triggered in more common circumstances
(e.g. a missing `volatile' or something like that, maybe?).

First thing: try to reproduce the problem with -DENABLE_CHECKING.
This may help us catch the problem at some earlier poin in the execution
(it's a long shot, but you never know).

Then try to narrow down the problematic source file: compile all files
with "gcc-4.2.3 -g" except for one (e.g. intervals.c) and see if you con
still reproduce the problem.  If you can, recompile intervals.c with
"gcc-4.2.3 -g" to double check that the problem then disappears.
If that's not that file, then use binary search to figure out which file
is causing trouble.


        Stefan