Re: JSON/YAML/TOML/etc. parsing performance

[Paul Eggert]

On 10/04/2017 01:03 AM, Eli Zaretskii wrote:
> Why didn't we add similar checks there?

If Emacs allocates the objects there is no problem, since it never 
allocates objects larger than PTRDIFF_MAX. Generally this is what 
gnutls.c and image.c do. There are places where they do need overflow 
checks (notably, image size calculation); in some cases the checks are 
there, in some they're old code that nobody has ever cleaned up and 
which undoubtedly has problems, and in either case the PTRDIFF_MAX 
versus SIZE_MAX issue is a bit of a sideshow as each image library has 
its own idea about what integer type to use.

We should not encourage more use of size_t within Emacs, as it's an 
unsigned type and unsigned types have the problems I mentioned.