Regex::is_match panics after successful creation with regex 0.2.4

[daboross]

Ran into this while building a dependency which uses bindgen. Seems the issue is with the regex at https://github.com/rust-lang-nursery/rust-bindgen/blob/04591f01d96a5c05e690dcf49d19d8e003eac7bf/src/clang.rs#L1060.

Reproduction:

extern crate regex;
fn main() {
    let thing = regex::Regex::new(r"typename type\-parameter\-\d+\-\d+::.+").unwrap();

    thing.is_match("test");
}

Error:

$ RUST_BACKTRACE=1 ./target/debug/reproduction-test 
thread 'main' panicked at 'assertion failed: haystack.len() >= self.pattern.len()', /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/literals.rs:602:9
stack backtrace:
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
             at /checkout/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
   1: std::sys_common::backtrace::print
             at /checkout/src/libstd/sys_common/backtrace.rs:68
             at /checkout/src/libstd/sys_common/backtrace.rs:57
   2: std::panicking::default_hook::{{closure}}
             at /checkout/src/libstd/panicking.rs:381
   3: std::panicking::default_hook
             at /checkout/src/libstd/panicking.rs:397
   4: std::panicking::rust_panic_with_hook
             at /checkout/src/libstd/panicking.rs:577
   5: std::panicking::begin_panic
             at /checkout/src/libstd/panicking.rs:538
   6: regex::literals::BoyerMooreSearch::find
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/literals.rs:602
   7: regex::dfa::Fsm::prefix_at
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/literals.rs:98
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/dfa.rs:1521
   8: regex::re_unicode::Regex::shortest_match_at
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/dfa.rs:708
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/dfa.rs:488
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/exec.rs:693
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/exec.rs:391
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/exec.rs:341
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/re_unicode.rs:633
   9: regex::re_unicode::Regex::is_match_at
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/re_unicode.rs:644
  10: regex::re_unicode::Regex::is_match
             at /home/daboross/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-0.2.4/src/re_unicode.rs:198
  11: reproduction_test::main
             at src/main.rs:5
  12: std::rt::lang_start::{{closure}}
             at /checkout/src/libstd/rt.rs:74
  13: std::panicking::try::do_call
             at /checkout/src/libstd/rt.rs:59
             at /checkout/src/libstd/panicking.rs:480
  14: __rust_maybe_catch_panic
             at /checkout/src/libpanic_unwind/lib.rs:101
  15: std::rt::lang_start_internal
             at /checkout/src/libstd/panicking.rs:459
             at /checkout/src/libstd/panic.rs:365
             at /checkout/src/libstd/rt.rs:58
  16: std::rt::lang_start
             at /checkout/src/libstd/rt.rs:74
  17: main
  18: __libc_start_main
  19: _start

Occurs with regex 0.2.4 on x86_64 linux, works fine with regex 0.2.3.

Thanks!

[BurntSushi]

Gah. Sorry. This was an oversight on my part. Fix incoming in #438. I'll get a new release out once that's merged.

[BurntSushi]

regex 0.2.5 is on crates.io with a fix to this. Thanks so much for reporting this!

[daboross]

Thank you!