bug#31138: Native json slower than json.el

[Eli Zaretskii]

> From: Alex Gramiak <agrambot@gmail.com>
> Cc: Eli Zaretskii <eliz@gnu.org>, Dmitry Gutov <dgutov@yandex.ru>
> Date: Mon, 22 Apr 2019 12:20:15 -0600
> 
> P.S. Would applying the following diff be okay? It's a simple
> optimization that avoids an overflow check (the sizeof comparison is
> optimized out even in -O0)

I don't understand what this optimizes, since AFAIU INT_TO_INTEGER
already produces a fixnum if possible.  It sounds like a step
backward, because the whole point of INT_TO_INTEGER is that the
programmer doesn't need to bother about the magnitude of the value.

> in the usual case of a JSON integer fitting into an EMACS_INT.

Not sure what you meant by "usual case".  Does this include a 32-bit
build of Emacs?