No line number in error message with try! macro

[eminence]

Playpen link: https://is.gd/eYoVIw

Using Stable or Beta, the error message looks like this:

<std macros>:5:8: 6:42 error: mismatched types:
[.. eliding text ..]
<anon>:6:17: 6:24 note: in this expansion of try! (defined in <std macros>)

The key part is that it tells me that line 6 is where the try expansion happens.

But when running with Nightly, this is the error message (in full):

error: mismatched types [--explain E0308]
 --> <std macros>:5:8
5 |> return $ crate :: result :: Result :: Err (
  |>        ^ expected struct `Foo`, found enum `std::result::Result`
<std macros>:5:8: 6:45: note: in this expansion of try! (defined in <std macros>)
note: expected type `Foo`
note:    found type `std::result::Result<_, _>`

error: aborting due to previous error
playpen: application terminated with error code 101

The expansion site (line 6) is missing from the error diagnostics. While the playpen uses the new-style diagnostics, this problem (the missing line number) applies to the old-style diagnostics too.

I'm not sure if this is only for try!, or if it is for all macros (I didn't test that)
I'm not sure exactly what version of rustc the playpen is at, but this issue is reproduced with rustc 1.10.0-nightly (cd6a40017 2016-05-16)

[Manishearth]

cc @nrc

[nrc]

cc @jonathandturner @nikomatsakis

[nikomatsakis]

ah I think I saw this bug when @jonathandturner and I were considering how best to render those stack traces... I feel like there was a simple logic bug in the "expand-macro-backtrace" code that led to it... @jonathandturner do you remember?

[eminence]

I tried to track this regression via bisection and I arrived at 01d2b4a as the culprit

[nikomatsakis]

note that #33730 has a fix