Re: WIP Incremental JSON Parser

On Thu, Apr 4, 2024 at 11:06 AM Nathan Bossart <nathandbossart@gmail.com> wrote:
> ../postgresql/src/common/jsonapi.c: In function ‘IsValidJsonNumber’:
> ../postgresql/src/common/jsonapi.c:2016:30: error: ‘dummy_lex.inc_state’ may be used uninitialized in this function
[-Werror=maybe-uninitialized]
>  2016 |  if (lex->incremental && !lex->inc_state->is_last_chunk &&
>       |                           ~~~^~~~~~~~~~~
> ../postgresql/src/common/jsonapi.c:2020:36: error: ‘dummy_lex.token_start’ may be used uninitialized in this function
[-Werror=maybe-uninitialized]
>  2020 |           lex->token_start, s - lex->token_start);
>       |                                 ~~~^~~~~~~~~~~~~

Ah, it hasn't figured out that the incremental path is disabled.
Zero-initializing the dummy_lex would be good regardless.

> ../postgresql/src/common/jsonapi.c:302:26: error: ‘numeric_error’ may be used uninitialized in this function
[-Werror=maybe-uninitialized]
>   302 |  return (!numeric_error) && (total_len == dummy_lex.input_length);
>       |         ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

For this case, though, I think it'd be good for API consistency if
*numeric_error were always set on return, instead of relying on the
caller to initialize.

--Jacob