[m-rev.] [Mercury-Language/mercury] Hashing-related fixes (#67)

[Julien Fischer]

On Tue, 30 Jul 2019, Zoltan Somogyi wrote:

> On Sun, 28 Jul 2019 18:35:56 -0700, wangp <notifications at github.com> wrote:
>
>> Merged #67 into master.
>
> I found today that a bootcheck failed three test cases, two of which may be
> related to this change:
>
>    hard_coded/hash_table_test
>    hard_coded/version_hash_table_test2
>    par_conj/pathological_right_recursion
>
> It *is* possible that this is a coincidence, because the bootcheck was with an Mmake.stage.params containing
>
>    EXTRA_MCFLAGS = -O0
>
> which I don't normally specify. (I was using a very old workspace.) These tests
> work just fine without the -O0.

I've just tried a bootcheck with those settings on my machine (x86_64
Linux, gcc 4.8.5).  Only one of the above is failing for me,
hard_coded/version_hash_table_test2, due to a detstack overflow.

Julien.