Re: Debian 12 gcc warning

On Tue, Aug 29, 2023 at 11:55:48AM +1200, David Rowley wrote:
> On Tue, 29 Aug 2023 at 07:37, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> > nargs = 0;
> > foreach(lc, args)
> > {
> > actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
> > }
>
> Does it still produce the warning if you form the above more like?
>
> nargs = list_length(args);
> for (int i = 0; i < nargs; i++)
> actual_arg_types[i] = exprType((Node *) list_nth(args, i));
>
> I'm just not sure if it's unable to figure out if at least nargs
> elements is set or if it won't be happy until all 100 elements are
> set.

I applied the attached patch but got the same warning:

clauses.c: In function ‘recheck_cast_function_args’:
clauses.c:4297:19: warning: ‘actual_arg_types’ may be used uninitialized [-Wmaybe-uninitialized]
4297 | rettype = enforce_generic_type_consistency(actual_arg_types,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4298 | declared_arg_types,
| ~~~~~~~~~~~~~~~~~~~
4299 | nargs,
| ~~~~~~
4300 | funcform->prorettype,
| ~~~~~~~~~~~~~~~~~~~~~
4301 | false);
| ~~~~~~
In file included from clauses.c:45:
../../../../src/include/parser/parse_coerce.h:82:17: note: by argument 1 of type ‘const Oid *’ {aka ‘const unsigned int *’} to ‘enforce_generic_type_consistency’ declared here
82 | extern Oid enforce_generic_type_consistency(const Oid *actual_arg_types,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
clauses.c:4279:33: note: ‘actual_arg_types’ declared here
4279 | Oid actual_arg_types[FUNC_MAX_ARGS];
| ^~~~~~~~~~~~~~~~

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

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