Re: tiny step toward threading: reduce dependence on setlocale()

On Wed, 2024-08-07 at 22:44 +0200, Peter Eisentraut wrote:
> But after this patch set, locale cannot be NULL anymore, so the third
> branch is obsolete.

...

> Second, there are a number of functions in like.c like the above that
> take separate arguments like pg_locale_t locale, bool locale_is_c.
> Because pg_locale_t now contains the locale_is_c information, these
> can
> be combined.

I believe these patches are correct, but the reasoning is fairly
complex:

1. Some MatchText variants are called with 0 for locale. But that's OK
because ...

2. A MatchText variant only cares about the locale if MATCH_LOWER(t) is
defined, and ...

3. Only one variant, SB_IMatchText() defines MATCH_LOWER(), and ...

4. SB_IMatchText() is called with a non-zero locale.

All of these are a bit confusing to follow because it's generated code.
#2 is particularly non-obvious, because "locale" is not even an
argument of the MATCH_LOWER(t) or GETCHAR(t) macros, it's taken
implicitly from the outer scope.

I don't think your patches cause this confusion, but is there a way you
can clarify some of this along the way?

Regards,
    Jeff Davis