diff --git a/compiler/rustc_passes/src/abi_test.rs b/compiler/rustc_passes/src/abi_test.rs
index 0c707b4ef9c..82392e72677 100644
--- a/compiler/rustc_passes/src/abi_test.rs
+++ b/compiler/rustc_passes/src/abi_test.rs
@@ -119,9 +119,13 @@ fn test_arg_abi_eq<'tcx>(
     abi2: &'tcx ArgAbi<'tcx, Ty<'tcx>>,
 ) -> bool {
     // Ideally we'd just compare the `mode`, but that is not enough -- for some modes LLVM will look
-    // at the type. Comparing the `mode` and `layout.abi` should catch basically everything though
-    // (except for tricky cases around unized types).
-    abi1.mode.eq_abi(&abi2.mode) && abi1.layout.abi.eq_up_to_validity(&abi2.layout.abi)
+    // at the type. Comparing the `mode` and `layout.abi` as well as size and alignment should catch
+    // basically everything though (except for tricky cases around unized types).
+    abi1.mode.eq_abi(&abi2.mode)
+        && abi1.layout.abi.eq_up_to_validity(&abi2.layout.abi)
+        && abi1.layout.size == abi2.layout.size
+        && abi1.layout.align.abi == abi2.layout.align.abi
+        && abi1.layout.is_sized() == abi2.layout.is_sized()
 }
 
 fn test_abi_eq<'tcx>(abi1: &'tcx FnAbi<'tcx, Ty<'tcx>>, abi2: &'tcx FnAbi<'tcx, Ty<'tcx>>) -> bool {
diff --git a/tests/ui/abi/debug.rs b/tests/ui/abi/debug.rs
index d08945ce3c2..9decb41d565 100644
--- a/tests/ui/abi/debug.rs
+++ b/tests/ui/abi/debug.rs
@@ -39,6 +39,9 @@ fn assoc_test(&self) { } //~ ERROR: fn_abi
 #[rustc_abi(assert_eq)]
 type TestAbiNe = (fn(u8), fn(u32)); //~ ERROR: ABIs are not compatible
 
+#[rustc_abi(assert_eq)]
+type TestAbiNeLarger = (fn([u8; 32]), fn([u32; 32])); //~ ERROR: ABIs are not compatible
+
 #[rustc_abi(assert_eq)]
 type TestAbiNeFloat = (fn(f32), fn(u32)); //~ ERROR: ABIs are not compatible
 
diff --git a/tests/ui/abi/debug.stderr b/tests/ui/abi/debug.stderr
index dffeef444f5..0feaf0971d8 100644
--- a/tests/ui/abi/debug.stderr
+++ b/tests/ui/abi/debug.stderr
@@ -508,6 +508,154 @@ error: ABIs are not compatible
 LL | type TestAbiNe = (fn(u8), fn(u32));
    | ^^^^^^^^^^^^^^
 
+error: ABIs are not compatible
+       left ABI = FnAbi {
+           args: [
+               ArgAbi {
+                   layout: TyAndLayout {
+                       ty: [u8; 32],
+                       layout: Layout {
+                           size: Size(32 bytes),
+                           align: AbiAndPrefAlign {
+                               abi: $SOME_ALIGN,
+                               pref: $SOME_ALIGN,
+                           },
+                           abi: Aggregate {
+                               sized: true,
+                           },
+                           fields: Array {
+                               stride: Size(1 bytes),
+                               count: 32,
+                           },
+                           largest_niche: None,
+                           variants: Single {
+                               index: 0,
+                           },
+                           max_repr_align: None,
+                           unadjusted_abi_align: $SOME_ALIGN,
+                       },
+                   },
+                   mode: Indirect {
+                       attrs: ArgAttributes {
+                           regular: NoAlias | NoCapture | NonNull | NoUndef,
+                           arg_ext: None,
+                           pointee_size: Size(32 bytes),
+                           pointee_align: Some(
+                               Align(1 bytes),
+                           ),
+                       },
+                       extra_attrs: None,
+                       on_stack: false,
+                   },
+               },
+           ],
+           ret: ArgAbi {
+               layout: TyAndLayout {
+                   ty: (),
+                   layout: Layout {
+                       size: Size(0 bytes),
+                       align: AbiAndPrefAlign {
+                           abi: $SOME_ALIGN,
+                           pref: $SOME_ALIGN,
+                       },
+                       abi: Aggregate {
+                           sized: true,
+                       },
+                       fields: Arbitrary {
+                           offsets: [],
+                           memory_index: [],
+                       },
+                       largest_niche: None,
+                       variants: Single {
+                           index: 0,
+                       },
+                       max_repr_align: None,
+                       unadjusted_abi_align: $SOME_ALIGN,
+                   },
+               },
+               mode: Ignore,
+           },
+           c_variadic: false,
+           fixed_count: 1,
+           conv: Rust,
+           can_unwind: $SOME_BOOL,
+       }
+       right ABI = FnAbi {
+           args: [
+               ArgAbi {
+                   layout: TyAndLayout {
+                       ty: [u32; 32],
+                       layout: Layout {
+                           size: Size(128 bytes),
+                           align: AbiAndPrefAlign {
+                               abi: $SOME_ALIGN,
+                               pref: $SOME_ALIGN,
+                           },
+                           abi: Aggregate {
+                               sized: true,
+                           },
+                           fields: Array {
+                               stride: Size(4 bytes),
+                               count: 32,
+                           },
+                           largest_niche: None,
+                           variants: Single {
+                               index: 0,
+                           },
+                           max_repr_align: None,
+                           unadjusted_abi_align: $SOME_ALIGN,
+                       },
+                   },
+                   mode: Indirect {
+                       attrs: ArgAttributes {
+                           regular: NoAlias | NoCapture | NonNull | NoUndef,
+                           arg_ext: None,
+                           pointee_size: Size(128 bytes),
+                           pointee_align: Some(
+                               Align(4 bytes),
+                           ),
+                       },
+                       extra_attrs: None,
+                       on_stack: false,
+                   },
+               },
+           ],
+           ret: ArgAbi {
+               layout: TyAndLayout {
+                   ty: (),
+                   layout: Layout {
+                       size: Size(0 bytes),
+                       align: AbiAndPrefAlign {
+                           abi: $SOME_ALIGN,
+                           pref: $SOME_ALIGN,
+                       },
+                       abi: Aggregate {
+                           sized: true,
+                       },
+                       fields: Arbitrary {
+                           offsets: [],
+                           memory_index: [],
+                       },
+                       largest_niche: None,
+                       variants: Single {
+                           index: 0,
+                       },
+                       max_repr_align: None,
+                       unadjusted_abi_align: $SOME_ALIGN,
+                   },
+               },
+               mode: Ignore,
+           },
+           c_variadic: false,
+           fixed_count: 1,
+           conv: Rust,
+           can_unwind: $SOME_BOOL,
+       }
+  --> $DIR/debug.rs:43:1
+   |
+LL | type TestAbiNeLarger = (fn([u8; 32]), fn([u32; 32]));
+   | ^^^^^^^^^^^^^^^^^^^^
+
 error: ABIs are not compatible
        left ABI = FnAbi {
            args: [
@@ -646,7 +794,7 @@ error: ABIs are not compatible
            conv: Rust,
            can_unwind: $SOME_BOOL,
        }
-  --> $DIR/debug.rs:43:1
+  --> $DIR/debug.rs:46:1
    |
 LL | type TestAbiNeFloat = (fn(f32), fn(u32));
    | ^^^^^^^^^^^^^^^^^^^
@@ -792,10 +940,10 @@ error: ABIs are not compatible
            conv: Rust,
            can_unwind: $SOME_BOOL,
        }
-  --> $DIR/debug.rs:47:1
+  --> $DIR/debug.rs:50:1
    |
 LL | type TestAbiNeSign = (fn(i32), fn(u32));
    | ^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 9 previous errors
+error: aborting due to 10 previous errors