POSIX describes WCHAR_MIN and WCHAR_MAX in stdint.h(0P), while
wchar.h(0P) only says "as described in stdint.h".
As there isn't a trivial path of "may make visible", just move it to a
shared header and include it from both files.
POSIX mandates that the macros contained in `stdint.h` be suitable for
use by the C preprocessor.
If we write `((size_t)-1)`, the C preprocessor will just skip the cast
and treat the value as `-1`. This means that we end up taking the wrong
branch in an `#if` directive like `#if SIZE_MAX > UINT32_MAX`.
This fixes building the LLVM port on i686.
x86_64 is an LP64 platform, so its `uint64_t` type is defined to be
`unsigned long`, not `unsigned long long` like on i686. This means that
the `UL` literal suffix should be used instead of `ULL`.
Furthermore, `uintptr_t` is 64 bits wide on x86_64, so defining
`UINTPTR_MAX` to be `UINT32_MAX` is also not correct.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
GCC installs a fixed version of the <limits.h> header as per https://gcc.gnu.org/onlinedocs/gcc/Fixed-Headers.html.
The fixed header doesn't include the target's <limits.h> which in turn means that some definitions (such as PATH_MAX)
aren't available. This change requires rebuilding the toolchain (Toolchain/BuildIt.sh).
This fixes the flatbuffers port.
The commit also removes some non-standard defines (U*_MIN) which don't appear to be used
anywhere. By definition they're always 0 though so they're not strictly necessary.
