On 11/28/2016 07:27 AM, Martin Jambor wrote:
Hi,
one of a number of symptoms of an otherwise unrelated HSA bug I've
been debugging today is gcc crashing or hanging in the C++ pretty
printer when attempting to emit a warning because dump_decl() ended up
in an infinite recursion calling itself on the DECL_ABSTRACT_ORIGIN of
the decl it was looking at, which was however the same thing. (It was
set to itself on purpose in set_decl_origin_self as a part of final
pass, the decl was being printed because it was itself an abstract
origin of another one).
If someone ever faces a similar problem, the following (untested)
patch might save them a bit of time. I have eventually decided not to
make it a checking-only assert because it is on a cold path and
because at release-build optimization levels, the tail-call is
optimized to a jump and thus an infinite loop if the described
situation happens, and I suppose an informative ICE is better tan that
even for users.
What do you think? Would it be reasonable for trunk even now or
should I queue it for the next stage1?
Thanks,
Martin
gcc/cp/
2016-11-28 Martin Jambor <mjam...@suse.cz>
* error.c (dump_decl): Add an assert that DECL_ABSTRACT_ORIGIN
is not the decl itself.
Given it's on an error/debug path it ought to be plenty safe for now.
What's more interesting is whether or not DECL_ABSTRACT_ORIGIN can
legitimately point to itself and if so, how is that happening.
I don't think we have a checker for the basic tree datastructures, but
maybe we ought to?
jeff
