Bug 60277 - Broken debugging in cases of mutli-level dependence and reflection (with linking)
Summary: Broken debugging in cases of mutli-level dependence and reflection (with link...
Alias: None
Product: Xamarin.Mac
Classification: Desktop
Component: mmp ()
Version: 4.0 (d15-5)
Hardware: PC Mac OS
: --- critical
Target Milestone: 15.7
Assignee: Sebastien Pouliot
Depends on:
Reported: 2017-10-19 19:11 UTC by Chris Hamons
Modified: 2018-01-12 22:41 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

Repro (3.55 MB, application/zip)
2017-10-19 19:11 UTC, Chris Hamons

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Description Chris Hamons 2017-10-19 19:11:28 UTC
Created attachment 25375 [details]

An internal customer reported this and I was able to create an synthetic sample that shows the problem (attached).

Steps to reproduce:

- Open attached sln
- Add breakpoints to both TheValue properties (one in each lib project)
- Debug
- Note only one is hit, the other has an empty sad circle because the pdb does not match the dll.
Comment 1 Chris Hamons 2017-10-19 19:13:43 UTC
Comment 2 Sebastien Pouliot 2018-01-09 20:49:39 UTC
Reverted with https://github.com/xamarin/xamarin-macios/pull/3188 but only in 15.6

It _might_ be (one of) the reason(s) why debugging sometime fails but we cannot reproduce the issues. If that's the case then quite a few people could end up with a (not so helpful) build error.

ref: https://bugzilla.xamarin.com/show_bug.cgi?id=60923

We need a better alternative for 15.7 (it's not reverted in master). Something like a _useful_ warning instead of a _generic_ error. 

Maybe it can be done on top of the existing PR ? or maybe another approach is needed.
Comment 3 Sebastien Pouliot 2018-01-11 16:22:28 UTC
Fixing this, differently, needs to work along
Comment 4 Sebastien Pouliot 2018-01-11 21:36:01 UTC
I'll double check the attached test case still works once I fix the issue.
Comment 5 Sebastien Pouliot 2018-01-12 21:06:02 UTC
without the fix (e.g. in 15.6) I hit only one breakpoint (bad)

with master/15.7 (original fix) I hit two breakpoints (good, but reverted for other issues)

with PR3203 [1] I hit two breakpoints (good and does not break existing projects)

[1] https://github.com/xamarin/xamarin-macios/pull/3203
Comment 6 Sebastien Pouliot 2018-01-12 22:41:11 UTC
Merged in master with https://github.com/xamarin/xamarin-macios/commit/3a851e2a639206bfef7fa9b22a69e8fd4c5d227c