implicit-hasher ICE

[quininer]

> cargo clippy -V
clippy 0.0.212 (316da7e 2019-07-07)

Running cargo clippy on this repo will report ICE.

[matthiaskrgr]

Some observations: if I inline the macro definition into lib.rs, the crash goes away.

std::collections::HashMap is imported in lib.rs (where the macro is used), the macro only uses HashMap.
When I make the macro use the full path std::collections::HashMap, the snippet no longer crashes.

So there might be some path resolution failure?

Backtrace:

    Checking ice-clippy-implicit-hasher v0.1.0 (/tmp/ice-clippy-implicit-hasher)
thread 'rustc' panicked at 'begin <= end (1 <= 0) when slicing ` `', src/libcore/str/mod.rs:2026:5
stack backtrace:
   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/backtrace-0.3.29/src/backtrace/libunwind.rs:88
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.aaakk.us.kg-1ecc6299db9ec823/backtrace-0.3.29/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:47
   3: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:36
   4: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:200
   5: std::panicking::default_hook
             at src/libstd/panicking.rs:214
   6: rustc::util::common::panic_hook
   7: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:481
   8: std::panicking::continue_panic_fmt
             at src/libstd/panicking.rs:384
   9: rust_begin_unwind
             at src/libstd/panicking.rs:311
  10: core::panicking::panic_fmt
             at src/libcore/panicking.rs:85
  11: core::str::slice_error_fail
             at src/libcore/str/mod.rs:0
  12: core::str::traits::<impl core::slice::SliceIndex<str> for core::ops::range::Range<usize>>::index::{{closure}}
  13: <clippy_lints::types::ImplicitHasher as rustc::lint::LateLintPass>::check_item::suggestion
  14: clippy_lints::utils::diagnostics::span_lint_and_then
  15: <clippy_lints::types::ImplicitHasher as rustc::lint::LateLintPass>::check_item
  16: <rustc::lint::context::LateLintPassObjects as rustc::lint::LateLintPass>::check_item
  17: rustc::hir::intravisit::Visitor::visit_nested_item
  18: rustc::hir::intravisit::walk_crate
  19: rustc::lint::context::late_lint_pass_crate
  20: rustc::lint::context::late_lint_crate
  21: rustc::util::common::time
  22: rustc::util::common::time
  23: __rust_maybe_catch_panic
             at src/libpanic_unwind/lib.rs:82
  24: <std::panic::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once
  25: __rust_maybe_catch_panic
             at src/libpanic_unwind/lib.rs:82
  26: rustc_interface::passes::analysis::{{closure}}
  27: rustc::util::common::time
  28: rustc_interface::passes::analysis
  29: rustc::ty::query::__query_compute::analysis
  30: rustc::dep_graph::graph::DepGraph::with_task_impl
  31: rustc::ty::query::plumbing::<impl rustc::ty::context::TyCtxt>::get_query
  32: rustc_interface::passes::BoxedGlobalCtxt::access::{{closure}}
  33: rustc_interface::passes::create_global_ctxt::{{closure}}
  34: rustc_interface::interface::run_compiler_in_existing_thread_pool
  35: std::thread::local::LocalKey<T>::with
  36: scoped_tls::ScopedKey<T>::set
  37: syntax::with_globals
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
query stack during panic:
#0 [analysis] running analysis passes on this crate
end of query stack
warning: parameter of type `HashMap` should be generalized over different hashers
 --> lib.rs:3:1
  |
3 | macros::foo!();
  | ^^^^^^^^^^^^^^^
  |
  = note: #[warn(clippy::implicit_hasher)] on by default
  = note: this warning originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)


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/blob/master/CONTRIBUTING.md#bug-reports

note: rustc 1.38.0-nightly (6e310f2ab 2019-07-07) running on x86_64-unknown-linux-gnu

note: compiler flags: -C debuginfo=2 -C incremental -C target-cpu=native --crate-type lib

note: some of the compiler flags provided by cargo are hidden

error: Could not compile `ice-clippy-implicit-hasher`.

To learn more, run the command again with --verbose.