30         // No padding check needed.  in derive_into_bytes_struct()
32         //   same as its only non-ZST field (meaning there's no padding outside  in derive_into_bytes_struct()
34         //   there's no padding in that field).  in derive_into_bytes_struct()
35         // - repr(packed): Any inter-field padding bytes are removed, meaning  in derive_into_bytes_struct()
36         //   that any padding bytes would need to come from the fields, all of  in derive_into_bytes_struct()
38         //   padding). Note that this holds regardless of other `repr`  in derive_into_bytes_struct()
45         //   inter-field padding.  in derive_into_bytes_struct()
48         // No padding check needed. A repr(C) struct with zero or one field has  in derive_into_bytes_struct()
49         // no padding unless #[repr(align)] explicitly adds padding, which we  in derive_into_bytes_struct()
56         // Since there are no generics, we can emit a padding check. All reprs  in derive_into_bytes_struct()
57         // guarantee that fields won't overlap [1], so the padding check is  in derive_into_bytes_struct()
74         // We can't use a padding check since there are generic type arguments.  in derive_into_bytes_struct()
77         // padding unless #[repr(align)] explicitly adds padding, which we check  in derive_into_bytes_struct()
151     // no padding.  in derive_into_bytes_union()