Remove use of MaybeUninit in our floar writers.

This used `::assume_init` which invoked undefined behavior.

- Closes #95

.github/workflows/Miri.yml

@@ -0,0 +1,19 @@
+name: Miri
+
+on: [workflow_dispatch]
+jobs:
+  Miri:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: nightly
+      - run: cargo check
+      - run: cargo build
+      - run: rustup component add --toolchain nightly miri
+      # Test with all features: this won't test the non-compact code paths however
+      - run: cargo miri test --all-features
+      - run: cargo miri test --features radix,format,write-integers,write-floats,parse-integers,parse-floats

CHANGELOG

@@ -7,11 +7,26 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Added fuzzing and miri code safety analysis to our CI pipelines.
+- Removed requirement of `alloc` in `no_std` ennvironments without the `write` feature.
+
 ### Changed
 
 - Updated the MSRV to 1.63.0 (1.65.0 for development).
 - Improved performance due to compiler regressions in rustc 1.81.0 and above.
 
+### Fixed
+
+- Removed use of undefined behavior in `MaybeUninit`.
+- Provide better safety documentation.
+- Parsing of Ruby float literals.
+- Performance regressions in Rust 1.81.0+.
+- Removed incorrect bounds checking in reading from iterators.
+- Overflow checking with integer parsing.
+- Writing `-0.0` with a leading `-`.
+
 ### Removed
 
 - Support for mips (MIPS), mipsel (MIPS LE), mips64 (MIPS64 BE), and mips64el (MIPS64 LE) on Linux.

lexical-write-float/src/compact.rs

@@ -25,7 +25,6 @@ use crate::float::{ExtendedFloat80, RawFloat};
 use crate::options::Options;
 use crate::shared;
 use crate::table::GRISU_POWERS_OF_TEN;
-use core::mem;
 use lexical_util::algorithm::rtrim_char_count;
 #[cfg(feature = "f16")]
 use lexical_util::bf16::bf16;
@@ -64,9 +63,7 @@ pub unsafe fn write_float<F: RawFloat, const FORMAT: u128>(
     debug_assert!(float >= F::ZERO);
 
     // Write our mantissa digits to a temporary buffer.
-    let digits: mem::MaybeUninit<[u8; 32]> = mem::MaybeUninit::uninit();
-    // SAFETY: safe, since we never read bytes that weren't written.
-    let mut digits = unsafe { digits.assume_init() };
+    let mut digits: [u8; 32] = [0u8; 32];
     let (digit_count, kappa, carried) = if float == F::ZERO {
         // SAFETY: safe since `digits.len() == 32`.
         unsafe { index_unchecked_mut!(digits[0]) = b'0' };

lexical-write-float/src/radix.rs

@@ -14,7 +14,6 @@
 
 use crate::options::{Options, RoundMode};
 use crate::shared;
-use core::mem;
 use lexical_util::algorithm::{ltrim_char_count, rtrim_char_count};
 use lexical_util::constants::{FormattedSize, BUFFER_SIZE};
 use lexical_util::digit::{char_to_digit_const, digit_to_char_const};
@@ -67,10 +66,7 @@ where
     // either way, with additional space for sign, decimal point and string
     // termination should be sufficient.
     const SIZE: usize = 2200;
-    let buffer: mem::MaybeUninit<[u8; SIZE]> = mem::MaybeUninit::uninit();
-    // SAFETY: safe, since we never read bytes that weren't written.
-    let mut buffer = unsafe { buffer.assume_init() };
-    //let buffer = buffer.as_mut_ptr();
+    let mut buffer = [0u8; SIZE];
     let initial_cursor: usize = SIZE / 2;
     let mut integer_cursor = initial_cursor;
     let mut fraction_cursor = initial_cursor;