# Function core::arch::x86::_mm_undefined_si128

1.27.0 · source ·

    pub unsafe fn _mm_undefined_si128() -> __m128i

Available on (x86 or x86-64) and target feature `sse2` and x86 only.
Expand description

Returns vector of type __m128i with indeterminate elements. Despite being “undefined”, this is some valid value and not equivalent to `mem::MaybeUninit`. In practice, this is equivalent to `mem::zeroed`.

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