error: layout_of(MissingPayloadField) = Layout {
           fields: Arbitrary {
               offsets: [
                   Size(0 bytes),
               ],
               memory_index: [
                   0,
               ],
           },
           variants: Multiple {
               tag: Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
               tag_encoding: Direct,
               tag_field: 0,
               variants: [
                   Layout {
                       fields: Arbitrary {
                           offsets: [
                               Size(1 bytes),
                           ],
                           memory_index: [
                               0,
                           ],
                       },
                       variants: Single {
                           index: 0,
                       },
                       abi: ScalarPair(
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=1,
                           },
                           Union {
                               value: Int(
                                   I8,
                                   false,
                               ),
                           },
                       ),
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(2 bytes),
                   },
                   Layout {
                       fields: Arbitrary {
                           offsets: [],
                           memory_index: [],
                       },
                       variants: Single {
                           index: 1,
                       },
                       abi: Aggregate {
                           sized: true,
                       },
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(1 bytes),
                   },
               ],
           },
           abi: ScalarPair(
               Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
               Union {
                   value: Int(
                       I8,
                       false,
                   ),
               },
           ),
           largest_niche: Some(
               Niche {
                   offset: Size(0 bytes),
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
           ),
           align: AbiAndPrefAlign {
               abi: Align(1 bytes),
               pref: $PREF_ALIGN,
           },
           size: Size(2 bytes),
       }
  --> $DIR/issue-96158-scalarpair-payload-might-be-uninit.rs:16:1
   |
LL | / pub enum MissingPayloadField {
LL | |     Some(u8),
LL | |     None
LL | | }
   | |_^

error: layout_of(CommonPayloadField) = Layout {
           fields: Arbitrary {
               offsets: [
                   Size(0 bytes),
               ],
               memory_index: [
                   0,
               ],
           },
           variants: Multiple {
               tag: Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
               tag_encoding: Direct,
               tag_field: 0,
               variants: [
                   Layout {
                       fields: Arbitrary {
                           offsets: [
                               Size(1 bytes),
                           ],
                           memory_index: [
                               0,
                           ],
                       },
                       variants: Single {
                           index: 0,
                       },
                       abi: ScalarPair(
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=1,
                           },
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=255,
                           },
                       ),
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(2 bytes),
                   },
                   Layout {
                       fields: Arbitrary {
                           offsets: [
                               Size(1 bytes),
                           ],
                           memory_index: [
                               0,
                           ],
                       },
                       variants: Single {
                           index: 1,
                       },
                       abi: ScalarPair(
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=1,
                           },
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=255,
                           },
                       ),
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(2 bytes),
                   },
               ],
           },
           abi: ScalarPair(
               Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
               Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=255,
               },
           ),
           largest_niche: Some(
               Niche {
                   offset: Size(0 bytes),
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
           ),
           align: AbiAndPrefAlign {
               abi: Align(1 bytes),
               pref: $PREF_ALIGN,
           },
           size: Size(2 bytes),
       }
  --> $DIR/issue-96158-scalarpair-payload-might-be-uninit.rs:25:1
   |
LL | / pub enum CommonPayloadField {
LL | |     A(u8),
LL | |     B(u8),
LL | | }
   | |_^

error: layout_of(CommonPayloadFieldIsMaybeUninit) = Layout {
           fields: Arbitrary {
               offsets: [
                   Size(0 bytes),
               ],
               memory_index: [
                   0,
               ],
           },
           variants: Multiple {
               tag: Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
               tag_encoding: Direct,
               tag_field: 0,
               variants: [
                   Layout {
                       fields: Arbitrary {
                           offsets: [
                               Size(1 bytes),
                           ],
                           memory_index: [
                               0,
                           ],
                       },
                       variants: Single {
                           index: 0,
                       },
                       abi: ScalarPair(
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=1,
                           },
                           Union {
                               value: Int(
                                   I8,
                                   false,
                               ),
                           },
                       ),
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(2 bytes),
                   },
                   Layout {
                       fields: Arbitrary {
                           offsets: [
                               Size(1 bytes),
                           ],
                           memory_index: [
                               0,
                           ],
                       },
                       variants: Single {
                           index: 1,
                       },
                       abi: ScalarPair(
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=1,
                           },
                           Union {
                               value: Int(
                                   I8,
                                   false,
                               ),
                           },
                       ),
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(2 bytes),
                   },
               ],
           },
           abi: ScalarPair(
               Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
               Union {
                   value: Int(
                       I8,
                       false,
                   ),
               },
           ),
           largest_niche: Some(
               Niche {
                   offset: Size(0 bytes),
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=1,
               },
           ),
           align: AbiAndPrefAlign {
               abi: Align(1 bytes),
               pref: $PREF_ALIGN,
           },
           size: Size(2 bytes),
       }
  --> $DIR/issue-96158-scalarpair-payload-might-be-uninit.rs:33:1
   |
LL | / pub enum CommonPayloadFieldIsMaybeUninit {
LL | |     A(u8),
LL | |     B(MaybeUninit<u8>),
LL | | }
   | |_^

error: layout_of(NicheFirst) = Layout {
           fields: Arbitrary {
               offsets: [
                   Size(0 bytes),
               ],
               memory_index: [
                   0,
               ],
           },
           variants: Multiple {
               tag: Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=4,
               },
               tag_encoding: Niche {
                   dataful_variant: 0,
                   niche_variants: 1..=2,
                   niche_start: 3,
               },
               tag_field: 0,
               variants: [
                   Layout {
                       fields: Arbitrary {
                           offsets: [
                               Size(0 bytes),
                               Size(1 bytes),
                           ],
                           memory_index: [
                               0,
                               1,
                           ],
                       },
                       variants: Single {
                           index: 0,
                       },
                       abi: ScalarPair(
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=2,
                           },
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=255,
                           },
                       ),
                       largest_niche: Some(
                           Niche {
                               offset: Size(0 bytes),
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=2,
                           },
                       ),
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(2 bytes),
                   },
                   Layout {
                       fields: Arbitrary {
                           offsets: [],
                           memory_index: [],
                       },
                       variants: Single {
                           index: 1,
                       },
                       abi: Aggregate {
                           sized: true,
                       },
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(0 bytes),
                   },
                   Layout {
                       fields: Arbitrary {
                           offsets: [],
                           memory_index: [],
                       },
                       variants: Single {
                           index: 2,
                       },
                       abi: Aggregate {
                           sized: true,
                       },
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(0 bytes),
                   },
               ],
           },
           abi: ScalarPair(
               Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=4,
               },
               Union {
                   value: Int(
                       I8,
                       false,
                   ),
               },
           ),
           largest_niche: Some(
               Niche {
                   offset: Size(0 bytes),
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=4,
               },
           ),
           align: AbiAndPrefAlign {
               abi: Align(1 bytes),
               pref: $PREF_ALIGN,
           },
           size: Size(2 bytes),
       }
  --> $DIR/issue-96158-scalarpair-payload-might-be-uninit.rs:41:1
   |
LL | / pub enum NicheFirst {
LL | |     A(HasNiche, u8),
LL | |     B,
LL | |     C
LL | | }
   | |_^

error: layout_of(NicheSecond) = Layout {
           fields: Arbitrary {
               offsets: [
                   Size(1 bytes),
               ],
               memory_index: [
                   0,
               ],
           },
           variants: Multiple {
               tag: Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=4,
               },
               tag_encoding: Niche {
                   dataful_variant: 0,
                   niche_variants: 1..=2,
                   niche_start: 3,
               },
               tag_field: 0,
               variants: [
                   Layout {
                       fields: Arbitrary {
                           offsets: [
                               Size(0 bytes),
                               Size(1 bytes),
                           ],
                           memory_index: [
                               0,
                               1,
                           ],
                       },
                       variants: Single {
                           index: 0,
                       },
                       abi: ScalarPair(
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=255,
                           },
                           Initialized {
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=2,
                           },
                       ),
                       largest_niche: Some(
                           Niche {
                               offset: Size(1 bytes),
                               value: Int(
                                   I8,
                                   false,
                               ),
                               valid_range: 0..=2,
                           },
                       ),
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(2 bytes),
                   },
                   Layout {
                       fields: Arbitrary {
                           offsets: [],
                           memory_index: [],
                       },
                       variants: Single {
                           index: 1,
                       },
                       abi: Aggregate {
                           sized: true,
                       },
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(0 bytes),
                   },
                   Layout {
                       fields: Arbitrary {
                           offsets: [],
                           memory_index: [],
                       },
                       variants: Single {
                           index: 2,
                       },
                       abi: Aggregate {
                           sized: true,
                       },
                       largest_niche: None,
                       align: AbiAndPrefAlign {
                           abi: Align(1 bytes),
                           pref: $PREF_ALIGN,
                       },
                       size: Size(0 bytes),
                   },
               ],
           },
           abi: ScalarPair(
               Union {
                   value: Int(
                       I8,
                       false,
                   ),
               },
               Initialized {
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=4,
               },
           ),
           largest_niche: Some(
               Niche {
                   offset: Size(1 bytes),
                   value: Int(
                       I8,
                       false,
                   ),
                   valid_range: 0..=4,
               },
           ),
           align: AbiAndPrefAlign {
               abi: Align(1 bytes),
               pref: $PREF_ALIGN,
           },
           size: Size(2 bytes),
       }
  --> $DIR/issue-96158-scalarpair-payload-might-be-uninit.rs:50:1
   |
LL | / pub enum NicheSecond {
LL | |     A(u8, HasNiche),
LL | |     B,
LL | |     C,
LL | | }
   | |_^

error: aborting due to 5 previous errors