Defining those aliases now may be a terrible idea because _BitInt (I'm
working on bringing it to C++) may be a genuine revamp of the integer
type system.

The existing fixed-width aliases have all the terrible implicit
conversions, integer promotions, weird overload behavior etc. that you
would expect, and so I would prefer not to perpetuate them. On some
platforms supported by GCC, int8_t is an alias for char (not even
signed char).

Maybe once _BitInt arrives (presumably C++29), we could think about
defining some shorthands for specific widths, like

> using u8 = bit_uint_t<8>;

Given the verbosity of bit_uint_t<8> (or bit_uint<8>), there could be
a good argument that if you use these types basically everywhere, you
want standard shorthands. For std::u8 vs. std::uint8_t, it's a hard
sell.

Anyhow, big things are happening in this area.

On Tue, 1 Jul 2025 at 18:24, Radu Ungureanu via Std-Proposals
<std-proposals_at_[hidden]> wrote:
>
> Aliasing stdint types like uint16_t to shorter names like u16 has become
> a very common practice. This trend has influenced other modern languages
> like Rust, Zig, Cpp2, Carbon and Odin to adopt this. On GitHub, u8 alone
> has lead to the same ~6k lines of code (counted with
> https://github.com/search?q=%22typedef+uint8_t+u8%22+language%3AC%2B%2B++NOT+is%3Afork&type=code
> and
> https://github.com/search?q=%22using+u8+%3D%22+language%3AC%2B%2B++NOT+is%3Afork&type=code).
> These names (int*_t) while precise, are quite verbose and cumbersome to
> use, especially in codebases where dealing with low-level code is the
> norm such as binary loaders or networking tools.
>
> I propose the following to be included in <cstdint>, a approach which
> has been inspired by std::literals:
>
> namespace std {
> namespace ints {
> using i8 = int8_t;
> using u8 = uint8_t;
> using i16 = int16_t;
> using u16 = uint16_t;
> using i32 = int32_t;
> using u32 = uint32_t;
> using i64 = int64_t;
> using u64 = uint64_t;
> using iN = intN_t;
> using uN = uintN_t;
> }
> }
>
> The typical usage of this would be as follows:
>
> using namespace std::ints;
> struct SomeFileFormatHeader {
> u16 magic;
> u32 checksum;
> u32 num_entries;
> // etc...
> }
>
> I have considered putting those in the same namespace as int*_t but that
> would break existing code that already defines those types using the
> help of stdint.
>
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