stabilize const_float_bits_conv

[RalfJung]

This stabilizes const_float_bits_conv, and thus fixes #72447. With #128596 having landed, this is entirely a libs-only question now.

impl f32 {
    pub const fn to_bits(self) -> u32;
    pub const fn from_bits(v: u32) -> Self;
    pub const fn to_be_bytes(self) -> [u8; 4];
    pub const fn to_le_bytes(self) -> [u8; 4]
    pub const fn to_ne_bytes(self) -> [u8; 4];
    pub const fn from_be_bytes(bytes: [u8; 4]) -> Self;
    pub const fn from_le_bytes(bytes: [u8; 4]) -> Self;
    pub const fn from_ne_bytes(bytes: [u8; 4]) -> Self;
}

impl f64 {
    pub const fn to_bits(self) -> u64;
    pub const fn from_bits(v: u64) -> Self;
    pub const fn to_be_bytes(self) -> [u8; 8];
    pub const fn to_le_bytes(self) -> [u8; 8]
    pub const fn to_ne_bytes(self) -> [u8; 8];
    pub const fn from_be_bytes(bytes: [u8; 8]) -> Self;
    pub const fn from_le_bytes(bytes: [u8; 8]) -> Self;
    pub const fn from_ne_bytes(bytes: [u8; 8]) -> Self;
}

Cc @rust-lang/wg-const-eval @rust-lang/libs-api

[rustbot]

r? @Mark-Simulacrum

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[rustbot]

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

[Amanieu]

This seems fine from the libs-api side, as long as wg-const-eval is happy with it.

@rfcbot fcp merge

[rfcbot]

Team member @Amanieu has proposed to merge this. The next step is review by the rest of the tagged team members:

• @Amanieu
• @BurntSushi
• @dtolnay
• @joshtriplett
• @m-ou-se

No concerns currently listed.

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

[rfcbot]

🔔 This is now entering its final comment period, as per the review above. 🔔

[rfcbot]

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed.

This will be merged soon.

[RalfJung]

@Amanieu can I take your comment above as "r=me once FCP passes"?

Otherwise, @Mark-Simulacrum this is now in your court. :)

[dtolnay]

@bors r+

[bors]

📌 Commit 19908ff has been approved by dtolnay

It is now in the queue for this repository.