Rollup merge of #99973 - RalfJung:layout-things, r=eddyb

Layout things

These two commits are pretty independent, but didn't seem worth doing individual PRs for:
- Always check that size is a multiple of align, even without debug assertions
- Change Layout debug printing to put `variants` last, since it often huge and not usually the part we are most interested in

Cc `@eddyb`

1 files changed, 121 insertions, 121 deletions

diff --git a/src/test/ui/layout/debug.stderr b/src/test/ui/layout/debug.stderr
index 7ba9657fcd6..c5e1c41d130 100644
--- a/src/test/ui/layout/debug.stderr
+++ b/src/test/ui/layout/debug.stderr
@@ -1,4 +1,12 @@
 error: layout_of(E) = Layout {
+           size: Size(12 bytes),
+           align: AbiAndPrefAlign {
+               abi: Align(4 bytes),
+               pref: $PREF_ALIGN,
+           },
+           abi: Aggregate {
+               sized: true,
+           },
            fields: Arbitrary {
                offsets: [
                    Size(0 bytes),
@@ -7,6 +15,16 @@ error: layout_of(E) = Layout {
                    0,
                ],
            },
+           largest_niche: Some(
+               Niche {
+                   offset: Size(0 bytes),
+                   value: Int(
+                       I32,
+                       false,
+                   ),
+                   valid_range: 0..=0,
+               },
+           ),
            variants: Multiple {
                tag: Initialized {
                    value: Int(
@@ -19,24 +37,30 @@ error: layout_of(E) = Layout {
                tag_field: 0,
                variants: [
                    Layout {
+                       size: Size(4 bytes),
+                       align: AbiAndPrefAlign {
+                           abi: Align(1 bytes),
+                           pref: $PREF_ALIGN,
+                       },
+                       abi: Aggregate {
+                           sized: true,
+                       },
                        fields: Arbitrary {
                            offsets: [],
                            memory_index: [],
                        },
+                       largest_niche: None,
                        variants: Single {
                            index: 0,
                        },
-                       abi: Aggregate {
-                           sized: true,
-                       },
-                       largest_niche: None,
+                   },
+                   Layout {
+                       size: Size(12 bytes),
                        align: AbiAndPrefAlign {
-                           abi: Align(1 bytes),
+                           abi: Align(4 bytes),
                            pref: $PREF_ALIGN,
                        },
-                       size: Size(4 bytes),
-                   },
-                   Layout {
+                       abi: Uninhabited,
                        fields: Arbitrary {
                            offsets: [
                                Size(4 bytes),
@@ -49,37 +73,13 @@ error: layout_of(E) = Layout {
                                2,
                            ],
                        },
+                       largest_niche: None,
                        variants: Single {
                            index: 1,
                        },
-                       abi: Uninhabited,
-                       largest_niche: None,
-                       align: AbiAndPrefAlign {
-                           abi: Align(4 bytes),
-                           pref: $PREF_ALIGN,
-                       },
-                       size: Size(12 bytes),
                    },
                ],
            },
-           abi: Aggregate {
-               sized: true,
-           },
-           largest_niche: Some(
-               Niche {
-                   offset: Size(0 bytes),
-                   value: Int(
-                       I32,
-                       false,
-                   ),
-                   valid_range: 0..=0,
-               },
-           ),
-           align: AbiAndPrefAlign {
-               abi: Align(4 bytes),
-               pref: $PREF_ALIGN,
-           },
-           size: Size(12 bytes),
        }
   --> $DIR/debug.rs:6:1
    |
@@ -87,20 +87,10 @@ LL | enum E { Foo, Bar(!, i32, i32) }
    | ^^^^^^
 
 error: layout_of(S) = Layout {
-           fields: Arbitrary {
-               offsets: [
-                   Size(0 bytes),
-                   Size(0 bytes),
-                   Size(4 bytes),
-               ],
-               memory_index: [
-                   1,
-                   0,
-                   2,
-               ],
-           },
-           variants: Single {
-               index: 0,
+           size: Size(8 bytes),
+           align: AbiAndPrefAlign {
+               abi: Align(4 bytes),
+               pref: $PREF_ALIGN,
            },
            abi: ScalarPair(
                Initialized {
@@ -118,12 +108,22 @@ error: layout_of(S) = Layout {
                    valid_range: 0..=4294967295,
                },
            ),
+           fields: Arbitrary {
+               offsets: [
+                   Size(0 bytes),
+                   Size(0 bytes),
+                   Size(4 bytes),
+               ],
+               memory_index: [
+                   1,
+                   0,
+                   2,
+               ],
+           },
            largest_niche: None,
-           align: AbiAndPrefAlign {
-               abi: Align(4 bytes),
-               pref: $PREF_ALIGN,
+           variants: Single {
+               index: 0,
            },
-           size: Size(8 bytes),
        }
   --> $DIR/debug.rs:9:1
    |
@@ -131,21 +131,21 @@ LL | struct S { f1: i32, f2: (), f3: i32 }
    | ^^^^^^^^
 
 error: layout_of(U) = Layout {
-           fields: Union(
-               2,
-           ),
-           variants: Single {
-               index: 0,
+           size: Size(8 bytes),
+           align: AbiAndPrefAlign {
+               abi: Align(4 bytes),
+               pref: $PREF_ALIGN,
            },
            abi: Aggregate {
                sized: true,
            },
+           fields: Union(
+               2,
+           ),
            largest_niche: None,
-           align: AbiAndPrefAlign {
-               abi: Align(4 bytes),
-               pref: $PREF_ALIGN,
+           variants: Single {
+               index: 0,
            },
-           size: Size(8 bytes),
        }
   --> $DIR/debug.rs:12:1
    |
@@ -153,6 +153,27 @@ LL | union U { f1: (i32, i32), f3: i32 }
    | ^^^^^^^
 
 error: layout_of(std::result::Result<i32, i32>) = Layout {
+           size: Size(8 bytes),
+           align: AbiAndPrefAlign {
+               abi: Align(4 bytes),
+               pref: $PREF_ALIGN,
+           },
+           abi: ScalarPair(
+               Initialized {
+                   value: Int(
+                       I32,
+                       false,
+                   ),
+                   valid_range: 0..=1,
+               },
+               Initialized {
+                   value: Int(
+                       I32,
+                       true,
+                   ),
+                   valid_range: 0..=4294967295,
+               },
+           ),
            fields: Arbitrary {
                offsets: [
                    Size(0 bytes),
@@ -161,6 +182,16 @@ error: layout_of(std::result::Result<i32, i32>) = Layout {
                    0,
                ],
            },
+           largest_niche: Some(
+               Niche {
+                   offset: Size(0 bytes),
+                   value: Int(
+                       I32,
+                       false,
+                   ),
+                   valid_range: 0..=1,
+               },
+           ),
            variants: Multiple {
                tag: Initialized {
                    value: Int(
@@ -173,16 +204,10 @@ error: layout_of(std::result::Result<i32, i32>) = Layout {
                tag_field: 0,
                variants: [
                    Layout {
-                       fields: Arbitrary {
-                           offsets: [
-                               Size(4 bytes),
-                           ],
-                           memory_index: [
-                               0,
-                           ],
-                       },
-                       variants: Single {
-                           index: 0,
+                       size: Size(8 bytes),
+                       align: AbiAndPrefAlign {
+                           abi: Align(4 bytes),
+                           pref: $PREF_ALIGN,
                        },
                        abi: ScalarPair(
                            Initialized {
@@ -200,14 +225,6 @@ error: layout_of(std::result::Result<i32, i32>) = Layout {
                                valid_range: 0..=4294967295,
                            },
                        ),
-                       largest_niche: None,
-                       align: AbiAndPrefAlign {
-                           abi: Align(4 bytes),
-                           pref: $PREF_ALIGN,
-                       },
-                       size: Size(8 bytes),
-                   },
-                   Layout {
                        fields: Arbitrary {
                            offsets: [
                                Size(4 bytes),
@@ -216,8 +233,16 @@ error: layout_of(std::result::Result<i32, i32>) = Layout {
                                0,
                            ],
                        },
+                       largest_niche: None,
                        variants: Single {
-                           index: 1,
+                           index: 0,
+                       },
+                   },
+                   Layout {
+                       size: Size(8 bytes),
+                       align: AbiAndPrefAlign {
+                           abi: Align(4 bytes),
+                           pref: $PREF_ALIGN,
                        },
                        abi: ScalarPair(
                            Initialized {
@@ -235,46 +260,21 @@ error: layout_of(std::result::Result<i32, i32>) = Layout {
                                valid_range: 0..=4294967295,
                            },
                        ),
+                       fields: Arbitrary {
+                           offsets: [
+                               Size(4 bytes),
+                           ],
+                           memory_index: [
+                               0,
+                           ],
+                       },
                        largest_niche: None,
-                       align: AbiAndPrefAlign {
-                           abi: Align(4 bytes),
-                           pref: $PREF_ALIGN,
+                       variants: Single {
+                           index: 1,
                        },
-                       size: Size(8 bytes),
                    },
                ],
            },
-           abi: ScalarPair(
-               Initialized {
-                   value: Int(
-                       I32,
-                       false,
-                   ),
-                   valid_range: 0..=1,
-               },
-               Initialized {
-                   value: Int(
-                       I32,
-                       true,
-                   ),
-                   valid_range: 0..=4294967295,
-               },
-           ),
-           largest_niche: Some(
-               Niche {
-                   offset: Size(0 bytes),
-                   value: Int(
-                       I32,
-                       false,
-                   ),
-                   valid_range: 0..=1,
-               },
-           ),
-           align: AbiAndPrefAlign {
-               abi: Align(4 bytes),
-               pref: $PREF_ALIGN,
-           },
-           size: Size(8 bytes),
        }
   --> $DIR/debug.rs:15:1
    |
@@ -282,9 +282,10 @@ LL | type Test = Result<i32, i32>;
    | ^^^^^^^^^
 
 error: layout_of(i32) = Layout {
-           fields: Primitive,
-           variants: Single {
-               index: 0,
+           size: Size(4 bytes),
+           align: AbiAndPrefAlign {
+               abi: Align(4 bytes),
+               pref: $PREF_ALIGN,
            },
            abi: Scalar(
                Initialized {
@@ -295,12 +296,11 @@ error: layout_of(i32) = Layout {
                    valid_range: 0..=4294967295,
                },
            ),
+           fields: Primitive,
            largest_niche: None,
-           align: AbiAndPrefAlign {
-               abi: Align(4 bytes),
-               pref: $PREF_ALIGN,
+           variants: Single {
+               index: 0,
            },
-           size: Size(4 bytes),
        }
   --> $DIR/debug.rs:18:1
    |