Cargo build fails on osx 10.9.5 with rustc head at b702bd4402

[ashee]

$ ./configure --prefix=/usr/local/Cellar/cargo/HEAD
$ RUST_BACKTRACE=1 make
"/usr/local/bin/rustc" -v
rustc 0.12.0-dev
target/snapshot/bin/cargo build --target x86_64-apple-darwin  
   Compiling flate2 v0.0.1 (https://github.com/alexcrichton/flate2-rs#2730aeaa)
   Compiling encoding v0.1.0 (https://github.com/lifthrasiir/rust-encoding#ea41c022)
   Compiling tar v0.0.1 (https://github.com/alexcrichton/tar-rs#e7c9952e)
   Compiling libgit2 v0.0.1 (https://github.com/alexcrichton/git2-rs#0e068d21)
Build failed, waiting for other jobs to finish...
Could not compile `libgit2`.

--- stdout
task 'rustc' failed at 'index out of bounds: the len is 57 but the index is 425', /private/tmp/rust-CbO1/src/libsyntax/lib.rs:1

stack backtrace:
   1:        0x103d4cac9 - rt::backtrace::imp::write::h4fc49b4d49e98b58ePq
   2:        0x103d4fe01 - failure::on_fail::hfdf68d2315fb5554S5q
   3:        0x103fd80f5 - unwind::begin_unwind_inner::ha069c794785abf32VRd
   4:        0x103fd7dc3 - unwind::begin_unwind_fmt::h1fe30e498bc10517nPd
   5:        0x103fd7b32 - rust_begin_unwind
   6:        0x10402c8fc - failure::fail_fmt::h75435008a2f3a7a9oqk
   7:        0x10402c7ce - failure::fail_bounds_check::h44be696c3aa60760Xok
   8:        0x10b11686a - util::interner::StrInterner::get::h6df8d40f98a8a601Ypa
   9:        0x10b12a5b8 - ast::Name::as_str::h8a6a85f3ad41a97auNb
  10:        0x10b207434 - parse::parser::Parser<'a>::lit_from_token::h56ca77bbee98a1d9f5M
  11:        0x10b20bb4c - parse::parser::Parser<'a>::parse_lit::h98296d0100df39c9j7M
  12:        0x10b20fafb - parse::parser::Parser<'a>::parse_bottom_expr::h86903ef52dd9df75CpN
  13:        0x10b2162cb - parse::parser::Parser<'a>::parse_prefix_expr::h381745a6f409e31fo7N
  14:        0x10b21689d - parse::parser::Parser<'a>::parse_assign_expr::h906ccb82bafe14edFfO
  15:        0x10b11b412 - parse::parser::Parser<'a>::parse_expr::h50002da6911f1838LrO
  16:        0x10433eade - parse_string::h843e40c3b8fb33377ua
  17:        0x10433d8e9 - expand_link_config::hcb649518d39987a5Cba
  18:        0x103541410 - ext::base::MacroExpanderFn.TTMacroExpander::expand::h684c541ea0b01025yk5
  19:        0x1035af63a - ext::expand::expand_item_mac::h9f64be252ccf854aklc
  20:        0x1035ac8fc - ext::expand::expand_item::h7fa5c41281d773905cc
  21:        0x1035b6e17 - fold::noop_fold_mod::closure.56235
  22:        0x1034f8ab7 - iter::Iterator::collect::h954723177506335140
  23:        0x1035b6088 - fold::Folder::fold_mod::h8527333888892530507
  24:        0x1035f16b3 - ext::expand::expand_crate::h501acc8f173b8aaa00c
  25:        0x101576544 - driver::driver::phase_2_configure_and_expand::closure.146095
  26:        0x1013043a5 - driver::driver::phase_2_configure_and_expand::hc14dac7f0481dd5evhx
  27:        0x101537f65 - driver::driver::compile_input::h0e7fbf587e605077Bax
  28:        0x1015b7d14 - driver::run_compiler::h6054d3d822ea9761S0A
  29:        0x1015b5eb6 - driver::run::closure.147677
  30:        0x100cdd51b - task::TaskBuilder<S>::try_future::closure.101699
  31:        0x100cdd413 - task::TaskBuilder<S>::spawn_internal::closure.101670
  32:        0x100c5385d - task::spawn_opts::closure.8555
  33:        0x10403bd4c - rust_try_inner
  34:        0x10403bd36 - rust_try
  35:        0x103fd50a7 - unwind::try::hbf4a1cbae321c012DGd
  36:        0x103fd4f3c - task::Task::run::h72a7c5a1b6e199eauWc
  37:        0x100c536b2 - task::spawn_opts::closure.8494
  38:        0x103fd704a - thread::thread_start::h3277d30828efff8fZgd
  39:     0x7fff8aa1c899 - _pthread_body
  40:     0x7fff8aa1c72a - _pthread_struct_init


--- stderr
error: internal compiler error: unexpected failure
note: the compiler hit an unexpected failure path. this is a bug.
note: we would appreciate a bug report: http://doc.rust-lang.org/complement-bugreport.html
note: run with `RUST_BACKTRACE=1` for a backtrace


To learn more, run the command again with --verbose.
make: *** [cargo-x86_64-apple-darwin] Error 101

[alexcrichton]

I think this is a dupe of rust-lang/rust#17289, with details of how to work around this here: rust-lang/rust#16029 (comment)