subgoal_abstraction test fails on windows

[memoryruins]

Currently, Chalk fails to build locally and on travis with the following error:

error: expected `*` or `+`
   --> src/fold.rs:440:35
    |
440 |     ($s:ident $([$($tt_args:tt)*])? { $($name:ident),* $(,)* } $($w:tt)*) => {
    |                                   ^
    |
    = note: `?` is not a macro repetition operator
error: expected `*` or `+`
   --> src/fold.rs:442:43
    |
442 |             @parse_tt_args($($($tt_args)*)?)
    |                                           ^
    |
    = note: `?` is not a macro repetition operator

I'm guessing this due to some recent changes in rust-lang/rust#48075, so I swapped the ?s with *s.
Chalk successfully builds and runs after the change; however, it fails the following test
https://github.com/rust-lang-nursery/chalk/blob/82c113efb5fbaf4e60d1c9d33ace05ba08b7631a/src/solve/slg/test.rs#L225-L242

---- solve::slg::test::subgoal_abstraction stdout ----
program {
trait Foo {  } struct Box < T > {  } impl < T > Foo for T where Box < T > :
Foo {  } }
----------------------------------------------------------------------
goal { exists < T > { T : Foo } }
thread 'solve::slg::test::subgoal_abstraction' panicked at 'attempt to subtract with overflow',

[eddyb]

Can you try a nightly from a month or so ago, one that supports ?, that is?
Then you can see if the test fails the same way.

[memoryruins]

July 23, 2018
chalk: Updating dependencies - pr opened, builds and passes tests on travis

July 24, 2018
rustc: 2018 edition ? Kleene operator - merged into rust master. Most likely not included in nightly-2018-07-24, since I believe most nightlies are built a day before the triple.

August 6, 2018
chalk: Updating dependencies - pr merged, chalk fails to build on master due to ? in macro

rustup triple	? in macro	* in macro
nightly-2018-07-24	test pass ✔️	test pass ✔️
nightly-2018-07-30	build error ❌	test pass ✔️
nightly-2018-08-01	build error ❌	test pass ✔️
nightly-2018-08-02	build error ❌	test pass ✔️
nightly-2018-08-03	build error ❌	test fail ❌
nightly-2018-08-06	build error ❌	test fail ❌

While using * in the macro, the test fails starting with nightly-2018-08-03.

[memoryruins]

The above tests were using the x86_64-pc-windows-msvc toolchain.

When returning online with my laptop, which uses the x86_64-unknown-linux-gnu toolchain, I tried the tests again (expecting to look into the stack trace). While using * in the macro, Chalk built and the tests passed.

Opening a PR with the macro change to see if it passes on travis CI as well, since it is also using linux-gnu toolchain. I'll check the stacktrace when next on the windows machine.

[memoryruins]

Looks like I should've opened the PR to begin with. It successfully builds and passes all tests on Travis CI.

Time to put Chalk on appveyor as well? At least, someone else try to see if they can recreate it on x86_64-pc-windows-msvc and nightly-2018-08-03+.

[memoryruins]

Checking in on x86_64-pc-windows-msvc again.
rustc 1.30.0-nightly (2ab3eba30 2018-09-14)

Backtrace from running cargo test:

failures:

---- test::slg::subgoal_abstraction stdout ----
program {
trait Foo {  } struct Box < T > {  } impl < T > Foo for T where Box < T > :
Foo {  } }
----------------------------------------------------------------------
goal { exists < T > { T : Foo } }
thread 'test::slg::subgoal_abstraction' panicked at 'attempt to subtract with overflow', C:\Users\Michael\.cargo\registry\src\github.com-1ecc6299db9ec823\stacker-0.1.3\src\lib.rs:79:9
stack backtrace:
   0: std::sys::windows::backtrace::set_frames
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\sys\windows\backtrace\mod.rs:104
   1: std::sys::windows::backtrace::set_frames
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\sys\windows\backtrace\mod.rs:104
   2: std::sys_common::backtrace::_print
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\sys_common\backtrace.rs:71
   3: std::sys_common::backtrace::_print
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\sys_common\backtrace.rs:71
   4: std::panicking::default_hook::{{closure}}
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\panicking.rs:211
   5: std::panicking::default_hook
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\panicking.rs:221
   6: std::panicking::rust_panic_with_hook
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\panicking.rs:477
   7: std::panicking::continue_panic_fmt
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\panicking.rs:391
   8: std::panicking::rust_begin_panic
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libstd\panicking.rs:326
   9: core::panicking::panic_fmt
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libcore\panicking.rs:77
  10: core::panicking::panic
             at /rustc/2ab3eba30741652ba538bc2fc2bba9d81a5c84c6\src/libcore\panicking.rs:52
  11: stacker::remaining_stack
             at C:\Users\Michael\.cargo\registry\src\github.com-1ecc6299db9ec823\stacker-0.1.3\src\lib.rs:79
  12: stacker::maybe_grow<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,closure>
             at C:\Users\Michael\.cargo\registry\src\github.com-1ecc6299db9ec823\stacker-0.1.3\src\lib.rs:66
  13: chalk_engine::maybe_grow_stack<closure,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-engine\src\lib.rs:325
  14: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1170
  15: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1078
  16: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  17: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  18: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  19: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  20: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  21: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  22: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  23: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  24: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  25: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  26: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  27: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  28: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  29: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  30: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  31: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  32: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  33: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  34: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  35: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  36: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  37: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  38: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  39: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  40: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  41: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  42: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  43: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  44: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  45: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  46: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  47: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  48: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  49: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  50: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  51: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  52: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  53: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  54: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  55: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  56: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  57: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  58: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  59: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  60: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  61: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  62: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  63: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  64: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  65: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  66: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  67: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  68: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  69: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  70: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  71: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  72: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  73: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  74: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  75: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  76: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  77: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  78: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  79: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  80: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  81: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  82: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  83: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  84: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  85: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  86: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  87: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  88: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  89: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  90: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  91: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100
  92: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::with_instantiated_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>
             at .\chalk-engine\src\logic.rs:277
  93: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_next_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:211
  94: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::ensure_answer_recursively<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:181
  95: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_positive_subgoal<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:988
  96: chalk_engine::forest::Forest<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>::pursue_strand<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:529
  97: chalk_engine::logic::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:1327
  98: chalk_engine::logic::{{impl}}::with_instantiated_strand::{{impl}}::with<chalk_solve::solve::slg::implementation::SlgContext,chalk_solve::solve::slg::implementation::SlgContext,chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>,chalk_solve::solve::slg::implementation::SlgContext>
             at .\chalk-engine\src\logic.rs:302
  99: chalk_solve::solve::slg::implementation::{{impl}}::instantiate_ex_clause<core::result::Result<(), chalk_engine::logic::StrandFail<chalk_solve::solve::slg::implementation::SlgContext>>,chalk_engine::logic::{{impl}}::with_instantiated_strand::With<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext, chalk_engine::logic::PursueStrand<chalk_solve::solve::slg::implementation::SlgContext, chalk_solve::solve::slg::implementation::SlgContext>>>
             at .\chalk-solve\src\solve\slg\implementation.rs:100


failures:
    test::slg::subgoal_abstraction

test result: FAILED. 139 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out

[memoryruins]

It's most likely an issue of the cpu on the windows machine I was testing on, rather than the toolchain itself.

https://github.com/rust-lang-nursery/chalk/blob/8b7284b61879d909e359436d76ca42e64f2cd114/chalk-engine/src/lib.rs#L314-L326

Since it appears already expected that stacker settings might be tweaked, and the original issue was sorted, closing this.