Bug 12822 - Linker issues with ASMX web services
Summary: Linker issues with ASMX web services
Alias: None
Product: iOS
Classification: Xamarin
Component: General ()
Version: 6.3.x
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2013-06-21 12:14 UTC by Neal
Modified: 2013-06-21 13:14 UTC (History)
2 users (show)

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

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Description Neal 2013-06-21 12:14:59 UTC

On the BETA channel testing async await implementation and using LINK ALL.  When doing so my ASMX web services don't work at all.  I recall seeing one warning or message during a compile about a linker issue with System.Web or System.Web.WebServices - can't remember and can't find it again.  Anyway, with LINK ALL the web services don't work, with Link SDK Assemblies it does.


P.S.  I've gone back to the stable channel as the app is crashing too much in the beta channel
Comment 1 Sebastien Pouliot 2013-06-21 13:14:22 UTC
That sounds normal. To use "Link all assemblies" you need to ensure that your own code preserve* its type/members that are used only thru reflection (because if they can't be found using static analysis the the linker will remove them). 

* This is identical to what Xamarin does on it's own (SDK) assemblies and why "Link SDK" works.

IOW you likely need to add some [Preserve] attributes on your types for "Link all assemblies" to work with web services (and/or WCF) since it's largely based on reflection. The linker automagically preserve the types with [Xml*] and [DataContract] attributes but that might not be enough for every application.

Note that this should be identical to using "Link all assemblies" with the stable version (if you want to try it again using the stable version). If not the please re-open the bug report with a self-contained test case so we can investigate why it differs.

p.s. please report crashers (along with stack traces) that you find using the beta channel. At some point, not too far away, the beta channel will become the new stable and, without bug reports, it could still contain the same issues you're presently facing.