[m-rev.] for post-commit review: fix mantis bug #543

[Julien Fischer]

On Mon, 24 Jan 2022, Zoltan Somogyi wrote:

> Fix name clash between C modules.
> 
> compiler/mercury_compile_llds_back_end.m:
>     In the usual case of generating low level C code, we generate names
>     for C modules that all have a numeric suffix. When compiling with
>     --everything-in-one-c-function, which is normally enabled only with -O6,
>     we generated C modules whose name did not include a numeric suffix.
>     In the case of three test cases, hard_coded/backend_external*.m,
>     this lack of a suffix caused clashes with the names of hand-written
>     C modules.
>
>     Fix this bug, Mantis #543, by always using numeric suffixes. Ensure this
>     by using the same machinery for generating names both with and without
>     --everything-in-one-c-function.
>
>     Give the predicates involved better names and more natural argument orders.

That's fine.

Julien.