ice: repr packed not a power of 2

[matthiaskrgr]

#[repr(packed(5))]
struct S 

rust-analyzer highlight < a.rs

thread 'main' panicked at crates/hir-def/src/data/adt.rs:131:56:
called `Result::unwrap()` on an `Err` value: `5` is not a power of 2
stack backtrace:
   0: rust_begin_unwind
             at /rustc/595bc6f00369475047538fdae1ff8cea692ac385/library/std/src/panicking.rs:645:5
   1: core::panicking::panic_fmt
             at /rustc/595bc6f00369475047538fdae1ff8cea692ac385/library/core/src/panicking.rs:72:14
   2: core::result::unwrap_failed
             at /rustc/595bc6f00369475047538fdae1ff8cea692ac385/library/core/src/result.rs:1649:5
   3: hir_def::data::adt::repr_from_value
   4: <hir_def::db::StructDataWithDiagnosticsQuery as salsa::plumbing::QueryFunction>::execute
   5: <salsa::derived::slot::Slot<hir_def::db::StructDataWithDiagnosticsQuery, salsa::derived::AlwaysMemoizeValue>>::execute
   6: <_ as hir_def::db::DefDatabase>::struct_data_with_diagnostics::__shim
   7: <ide_db::RootDatabase as hir_def::db::DefDatabase>::struct_data_with_diagnostics
   8: <salsa::derived::slot::Slot<hir_def::db::StructDataQuery, salsa::derived::AlwaysMemoizeValue>>::execute
   9: <_ as hir_def::db::DefDatabase>::struct_data::__shim
  10: <hir::Struct as hir::HasVisibility>::visibility
  11: <hir::Adt as hir::HasVisibility>::visibility
  12: <ide_db::defs::Definition>::visibility
  13: ide::syntax_highlighting::highlight::highlight_def
  14: ide::syntax_highlighting::highlight
  15: <ide::Analysis>::highlight_as_html
  16: <rust_analyzer::cli::flags::Highlight>::run
  17: rust_analyzer::main
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

rust-analyzer 1.77.0-nightly (595bc6f 2024-01-05)