#[repr(align)] with no argument to align leads to ICE on Nightly/Beta. #85713
Description
Code
#[repr(align)] pub struct Foo;Meta
Version: 1.54.0-nightly (2021-05-25 ff2c947)
Found this on the Rust playground: reproducing link. Not sure how to get the verbose version output from the playground.
Error output
Compiling playground v0.0.1 (/playground) error: internal compiler error: unrecognized representation hint --> src/lib.rs:2:8 | 2 | #[repr(align)] | ^^^^^ | = note: delayed at compiler/rustc_attr/src/builtin.rs:940:32 thread 'rustc' panicked at 'no errors encountered even though `delay_span_bug` issued', compiler/rustc_errors/src/lib.rs:1021:13 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace error: internal compiler error: unexpected panic note: the compiler unexpectedly panicked. this is a bug. note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md note: rustc 1.54.0-nightly (ff2c947c0 2021-05-25) running on x86_64-unknown-linux-gnu note: compiler flags: -C embed-bitcode=no -C codegen-units=1 -C debuginfo=2 --crate-type lib note: some of the compiler flags provided by cargo are hidden query stack during panic: end of query stack error: could not compile `playground` To learn more, run the command again with --verbose. Backtrace
thread 'rustc' panicked at 'no errors encountered even though `delay_span_bug` issued', compiler/rustc_errors/src/lib.rs:1021:13 stack backtrace: 0: rust_begin_unwind at /rustc/ff2c947c00f867b9f012e28ba88cecfbe556f904/library/std/src/panicking.rs:515:5 1: std::panicking::begin_panic_fmt at /rustc/ff2c947c00f867b9f012e28ba88cecfbe556f904/library/std/src/panicking.rs:457:5 2: rustc_errors::HandlerInner::flush_delayed 3: <rustc_errors::HandlerInner as core::ops::drop::Drop>::drop 4: core::ptr::drop_in_place<rustc_session::parse::ParseSess> 5: <alloc::rc::Rc<T> as core::ops::drop::Drop>::drop 6: core::ptr::drop_in_place<rustc_interface::interface::Compiler> 7: rustc_span::with_source_map 8: scoped_tls::ScopedKey<T>::set note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.