VaArgSafe in std::ffi - Rust
Description: Types that are valid to read using `VaList::arg`.

## VaArgSafe

# Trait VaArgSafe

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    pub unsafe trait VaArgSafe: Sealed { }

🔬This is a nightly-only experimental API. (`c_variadic` #44930)
Expand description

Types that are valid to read using `VaList::arg`.

## §Safety

The standard library implements this trait for primitive types that are expected to have a variable argument application-binary interface (ABI) on all platforms.

When C passes variable arguments, integers smaller than `c_int` and floats smaller than `c_double` are implicitly promoted to `c_int` and `c_double` respectively. Implementing this trait for types that are subject to this promotion rule is invalid.

## Implementors§

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### impl VaArgSafe for f64

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### impl VaArgSafe for i32

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### impl VaArgSafe for i64

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### impl VaArgSafe for isize

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### impl VaArgSafe for u32

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### impl VaArgSafe for u64

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### impl VaArgSafe for usize

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### impl<T> VaArgSafe for *const T

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### impl<T> VaArgSafe for *mut T