diff --git a/library/stdarch/crates/core_arch/src/x86/mod.rs b/library/stdarch/crates/core_arch/src/x86/mod.rs
index 78a3e23179ba..46bf4037bda6 100644
--- a/library/stdarch/crates/core_arch/src/x86/mod.rs
+++ b/library/stdarch/crates/core_arch/src/x86/mod.rs
@@ -344,7 +344,7 @@ types! {
 
 /// The `__mmask16` type used in AVX-512 intrinsics, a 16-bit integer
 #[allow(non_camel_case_types)]
-pub type __mmask16 = i16;
+pub type __mmask16 = u16;
 
 #[cfg(test)]
 mod test;