diff --git a/src/tools/miri/tests/fail/intrinsics/simd-div-by-zero.rs b/src/tools/miri/tests/fail/intrinsics/simd-div-by-zero.rs
index ba474332b811c..57a9b66d8ecde 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-div-by-zero.rs
+++ b/src/tools/miri/tests/fail/intrinsics/simd-div-by-zero.rs
@@ -4,12 +4,12 @@ use std::intrinsics::simd::simd_div;
 
 #[repr(simd)]
 #[allow(non_camel_case_types)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 
 fn main() {
     unsafe {
-        let x = i32x2(1, 1);
-        let y = i32x2(1, 0);
+        let x = i32x2([1, 1]);
+        let y = i32x2([1, 0]);
         simd_div(x, y); //~ERROR: Undefined Behavior: dividing by zero
     }
 }
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-div-overflow.rs b/src/tools/miri/tests/fail/intrinsics/simd-div-overflow.rs
index d01e41de0e4be..8ffc2669828c4 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-div-overflow.rs
+++ b/src/tools/miri/tests/fail/intrinsics/simd-div-overflow.rs
@@ -4,12 +4,12 @@ use std::intrinsics::simd::simd_div;
 
 #[repr(simd)]
 #[allow(non_camel_case_types)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 
 fn main() {
     unsafe {
-        let x = i32x2(1, i32::MIN);
-        let y = i32x2(1, -1);
+        let x = i32x2([1, i32::MIN]);
+        let y = i32x2([1, -1]);
         simd_div(x, y); //~ERROR: Undefined Behavior: overflow in signed division
     }
 }
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-reduce-invalid-bool.rs b/src/tools/miri/tests/fail/intrinsics/simd-reduce-invalid-bool.rs
index a194f0dd18aa8..ea0f908d996ff 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-reduce-invalid-bool.rs
+++ b/src/tools/miri/tests/fail/intrinsics/simd-reduce-invalid-bool.rs
@@ -4,11 +4,11 @@ use std::intrinsics::simd::simd_reduce_any;
 
 #[repr(simd)]
 #[allow(non_camel_case_types)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 
 fn main() {
     unsafe {
-        let x = i32x2(0, 1);
+        let x = i32x2([0, 1]);
         simd_reduce_any(x); //~ERROR: must be all-0-bits or all-1-bits
     }
 }
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-rem-by-zero.rs b/src/tools/miri/tests/fail/intrinsics/simd-rem-by-zero.rs
index cd1e4b8162b36..21c9520efc48a 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-rem-by-zero.rs
+++ b/src/tools/miri/tests/fail/intrinsics/simd-rem-by-zero.rs
@@ -4,12 +4,12 @@ use std::intrinsics::simd::simd_rem;
 
 #[repr(simd)]
 #[allow(non_camel_case_types)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 
 fn main() {
     unsafe {
-        let x = i32x2(1, 1);
-        let y = i32x2(1, 0);
+        let x = i32x2([1, 1]);
+        let y = i32x2([1, 0]);
         simd_rem(x, y); //~ERROR: Undefined Behavior: calculating the remainder with a divisor of zero
     }
 }
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-select-bitmask-invalid.rs b/src/tools/miri/tests/fail/intrinsics/simd-select-bitmask-invalid.rs
index 96802fae49c23..409098ac3b5df 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-select-bitmask-invalid.rs
+++ b/src/tools/miri/tests/fail/intrinsics/simd-select-bitmask-invalid.rs
@@ -5,11 +5,11 @@ use std::intrinsics::simd::simd_select_bitmask;
 #[repr(simd)]
 #[allow(non_camel_case_types)]
 #[derive(Copy, Clone)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 
 fn main() {
     unsafe {
-        let x = i32x2(0, 1);
+        let x = i32x2([0, 1]);
         simd_select_bitmask(0b11111111u8, x, x); //~ERROR: bitmask less than 8 bits long must be filled with 0s for the remaining bits
     }
 }
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-select-invalid-bool.rs b/src/tools/miri/tests/fail/intrinsics/simd-select-invalid-bool.rs
index 388fb2e2a84ae..a81ce95ada62f 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-select-invalid-bool.rs
+++ b/src/tools/miri/tests/fail/intrinsics/simd-select-invalid-bool.rs
@@ -5,11 +5,11 @@ use std::intrinsics::simd::simd_select;
 #[repr(simd)]
 #[allow(non_camel_case_types)]
 #[derive(Copy, Clone)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 
 fn main() {
     unsafe {
-        let x = i32x2(0, 1);
+        let x = i32x2([0, 1]);
         simd_select(x, x, x); //~ERROR: must be all-0-bits or all-1-bits
     }
 }
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-shl-too-far.rs b/src/tools/miri/tests/fail/intrinsics/simd-shl-too-far.rs
index 12aa7c10af4e4..ed317254ee66c 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-shl-too-far.rs
+++ b/src/tools/miri/tests/fail/intrinsics/simd-shl-too-far.rs
@@ -4,12 +4,12 @@ use std::intrinsics::simd::simd_shl;
 
 #[repr(simd)]
 #[allow(non_camel_case_types)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 
 fn main() {
     unsafe {
-        let x = i32x2(1, 1);
-        let y = i32x2(100, 0);
+        let x = i32x2([1, 1]);
+        let y = i32x2([100, 0]);
         simd_shl(x, y); //~ERROR: overflowing shift by 100 in `simd_shl` in lane 0
     }
 }
diff --git a/src/tools/miri/tests/fail/intrinsics/simd-shr-too-far.rs b/src/tools/miri/tests/fail/intrinsics/simd-shr-too-far.rs
index ada7cf408c4ed..5d2ff1b82ed06 100644
--- a/src/tools/miri/tests/fail/intrinsics/simd-shr-too-far.rs
+++ b/src/tools/miri/tests/fail/intrinsics/simd-shr-too-far.rs
@@ -4,12 +4,12 @@ use std::intrinsics::simd::simd_shr;
 
 #[repr(simd)]
 #[allow(non_camel_case_types)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 
 fn main() {
     unsafe {
-        let x = i32x2(1, 1);
-        let y = i32x2(20, 40);
+        let x = i32x2([1, 1]);
+        let y = i32x2([20, 40]);
         simd_shr(x, y); //~ERROR: overflowing shift by 40 in `simd_shr` in lane 1
     }
 }
diff --git a/src/tools/miri/tests/pass/simd-intrinsic-generic-elements.rs b/src/tools/miri/tests/pass/simd-intrinsic-generic-elements.rs
index 4a87f8c3ca720..9cf0c2ddef333 100644
--- a/src/tools/miri/tests/pass/simd-intrinsic-generic-elements.rs
+++ b/src/tools/miri/tests/pass/simd-intrinsic-generic-elements.rs
@@ -3,22 +3,22 @@
 #[repr(simd)]
 #[derive(Copy, Clone, Debug, PartialEq)]
 #[allow(non_camel_case_types)]
-struct i32x2(i32, i32);
+struct i32x2([i32; 2]);
 #[repr(simd)]
 #[derive(Copy, Clone, Debug, PartialEq)]
 #[allow(non_camel_case_types)]
-struct i32x4(i32, i32, i32, i32);
+struct i32x4([i32; 4]);
 #[repr(simd)]
 #[derive(Copy, Clone, Debug, PartialEq)]
 #[allow(non_camel_case_types)]
-struct i32x8(i32, i32, i32, i32, i32, i32, i32, i32);
+struct i32x8([i32; 8]);
 
 fn main() {
-    let _x2 = i32x2(20, 21);
-    let _x4 = i32x4(40, 41, 42, 43);
-    let _x8 = i32x8(80, 81, 82, 83, 84, 85, 86, 87);
+    let _x2 = i32x2([20, 21]);
+    let _x4 = i32x4([40, 41, 42, 43]);
+    let _x8 = i32x8([80, 81, 82, 83, 84, 85, 86, 87]);
 
-    let _y2 = i32x2(120, 121);
-    let _y4 = i32x4(140, 141, 142, 143);
-    let _y8 = i32x8(180, 181, 182, 183, 184, 185, 186, 187);
+    let _y2 = i32x2([120, 121]);
+    let _y4 = i32x4([140, 141, 142, 143]);
+    let _y8 = i32x8([180, 181, 182, 183, 184, 185, 186, 187]);
 }