Failed to get crate data when compiling proc macro crate with --target

[Canop]

Meta

rustc 1.52.1 (9bc8c42bb 2021-05-09)
binary: rustc
commit-hash: 9bc8c42bb2f19e745a63f3445f1ac248fb015e53
commit-date: 2021-05-09
host: x86_64-unknown-linux-gnu
release: 1.52.1
LLVM version: 12.0.0

I also tried with rustc 1.54.0-nightly (b663c0f 2021-05-29), and I got the same error.

Reproduction

git clone https://github.com/Canop/lazy-regex.git
cd lazy-regex
rustup target add wasm32-unknown-unknown
cargo build --target=wasm32-unknown-unknown

Error output

RUST_BACKTRACE=1 cargo build --target=wasm32-unknown-unknown --verbose
       Fresh unicode-xid v0.2.2
       Fresh regex-syntax v0.6.25
       Fresh once_cell v1.7.2
       Fresh proc-macro2 v1.0.26
       Fresh memchr v2.4.0
       Fresh quote v1.0.9
       Fresh aho-corasick v0.7.18
       Fresh syn v1.0.72
       Fresh regex v1.5.4
       Fresh lazy-regex-proc_macros v2.0.1 (/home/dys/dev/lazy-regex/src/proc_macros)
   Compiling lazy-regex v2.0.1 (/home/dys/dev/lazy-regex)
     Running `rustc --crate-name lazy_regex --edition=2018 src/lib.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type lib --emit=dep-info,metadata,link -C embed-bitcode=no -C debuginfo=2 -C metadata=7383ed1e4040a672 -C extra-filename=-7383ed1e4040a672 --out-dir /home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/deps --target wasm32-unknown-unknown -C incremental=/home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/incremental -L dependency=/home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/deps -L dependency=/home/dys/dev/lazy-regex/target/debug/deps --extern proc_macros=/home/dys/dev/lazy-regex/target/debug/deps/liblazy_regex_proc_macros-925a4044a7b9d421.so --extern once_cell=/home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/deps/libonce_cell-dbc6fec029817a84.rmeta --extern regex=/home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/deps/libregex-3d889e62663e24c7.rmeta`
thread 'rustc' panicked at 'Failed to get crate data for crate16', compiler/rustc_metadata/src/creader.rs:139:32
stack backtrace:
   0: rust_begin_unwind
             at /rustc/b663c0f4f6ff84a8c9df0f708e1f8d628330d973/library/std/src/panicking.rs:515:5
   1: std::panicking::begin_panic_fmt
             at /rustc/b663c0f4f6ff84a8c9df0f708e1f8d628330d973/library/std/src/panicking.rs:457:5
   2: rustc_metadata::creader::CrateLoader::maybe_resolve_crate
   3: rustc_metadata::creader::CrateLoader::maybe_process_path_extern
   4: rustc_resolve::Resolver::extern_prelude_get
   5: rustc_resolve::macros::<impl rustc_resolve::Resolver>::early_resolve_ident_in_lexical_scope
   6: rustc_resolve::Resolver::resolve_path_with_ribs::{{closure}}
   7: rustc_resolve::Resolver::resolve_path_with_ribs
   8: rustc_resolve::imports::ImportResolver::resolve_imports
   9: rustc_resolve::macros::<impl rustc_expand::base::ResolverExpand for rustc_resolve::Resolver>::resolve_imports
  10: rustc_expand::expand::MacroExpander::fully_expand_fragment
  11: rustc_expand::expand::MacroExpander::expand_crate
  12: rustc_session::utils::<impl rustc_session::session::Session>::time
  13: rustc_interface::passes::configure_and_expand_inner
  14: rustc_interface::passes::configure_and_expand::{{closure}}
  15: rustc_data_structures::box_region::PinnedGenerator<I,A,R>::new
  16: rustc_interface::passes::configure_and_expand
  17: rustc_interface::queries::Queries::expansion
  18: rustc_span::with_session_globals
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose 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 (b663c0f4f 2021-05-29) running on x86_64-unknown-linux-gnu

note: compiler flags: -C embed-bitcode=no -C debuginfo=2 -C incremental --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 `lazy-regex`

Caused by:
  process didn't exit successfully: `rustc --crate-name lazy_regex --edition=2018 src/lib.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type lib --emit=dep-info,metadata,link -C embed-bitcode=no -C debuginfo=2 -C metadata=7383ed1e4040a672 -C extra-filename=-7383ed1e4040a672 --out-dir /home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/deps --target wasm32-unknown-unknown -C incremental=/home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/incremental -L dependency=/home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/deps -L dependency=/home/dys/dev/lazy-regex/target/debug/deps --extern proc_macros=/home/dys/dev/lazy-regex/target/debug/deps/liblazy_regex_proc_macros-925a4044a7b9d421.so --extern once_cell=/home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/deps/libonce_cell-dbc6fec029817a84.rmeta --extern regex=/home/dys/dev/lazy-regex/target/wasm32-unknown-unknown/debug/deps/libregex-3d889e62663e24c7.rmeta` (exit status: 101)

Details

The involved crate is a proc-macro : https://github.com/Canop/lazy-regex.git

There's no problem when not using --target.

I reproduced the same problem with an app using it (broot) when compiling with a target (not just wasm), but not when compiling for the local implied target.

[Canop]

@AlephAlpha found a workaround: https://github.com/Canop/lazy-regex/pull/6/files

This issue should still probably stay open because of the rustc crash and because the problem isn't clear.

[jyn514]

Duplicate of #85386 (which was in turn a narrow case of #56935).