The largest value that a size_t can hold for the target
platform.
Defined in <SDL3/SDL_stdinc.h>
#define SDL_SIZE_MAX SIZE_MAXsize_t is generally the same size as a pointer in modern
times, but this can get weird on very old and very esoteric machines.
For example, on a 16-bit Intel 286, you might have a 32-bit "far"
pointer (16-bit segment plus 16-bit offset), but size_t is
16 bits, because it can only deal with the offset into an individual
segment.
In modern times, it's generally expected to cover an entire linear address space. But be careful!
This macro is available since SDL 3.2.0.