Bug 24157 - No compilation error for wrong Export attribute
Summary: No compilation error for wrong Export attribute
Alias: None
Product: Xamarin.Mac
Classification: Desktop
Component: Library (Xamarin.Mac.dll) ()
Version: Master
Hardware: Macintosh Mac OS
: Normal normal
Target Milestone: ---
Assignee: Chris Hamons
Depends on:
Reported: 2014-10-30 10:32 UTC by Rustam Zaitov
Modified: 2014-11-05 02:55 UTC (History)
3 users (show)

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

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Description Rustam Zaitov 2014-10-30 10:32:40 UTC
If I decorated method with [Export] attribute and provided mismatched selector I will not receive any error until runtime.

If I do the same for iOS (building for device, not for simulator) I will receive build error like follow:
Error MT4117: The registrar found a signature mismatch in the method 'AttributeUsageIOS.AppDelegate.MyTestMethod2' - the selector 'someSelector2' indicates the method takes 0 parameters, while the managed method has 2 parameters. (MT4117)

I will NOT receive this error if I build for simulator. As I understand this relative to AOT. For iOS this is not critical because during developing you will build your app for device often, so you will get this error quickly. But if I develop mac app I will receive this error only during execution.

Can we fix this for Mac? I mean I would like to get build error instead of runtime error.
Comment 1 Ram Chandra 2014-11-04 10:53:02 UTC
I have checked this issue and I am able to reproduce this issue.

When I check the decorated method with [Export] attribute and provided mismatched selector I observed that I am not getting any build error with Xamarin.Mac but when I check the same with iOS I am getting following build error.

"Error MT4117: The registrar found a signature mismatch in the method 'Test.AppDelegate.Apply' - the selector 'apply' indicates the method takes 0 parameters, while the managed method has 1 parameters. (MT4117) "

Screencast with Mac: http://www.screencast.com/t/NpB1ppIZ4
Screencast with iOS: http://www.screencast.com/t/cdi17ZwFkO

Environment Info:

=== Xamarin Studio ===

Version 5.5.3 (build 6)
Installation UUID: 6ea47b0d-1852-4aaf-808d-373ff0a5002b
	Mono 3.10.0 ((detached/e204655)
	GTK+ 2.24.23 (Raleigh theme)

	Package version: 310000023

=== Apple Developer Tools ===

Xcode 6.0.1 (6528)
Build 6A317

=== Xamarin.Mac ===

Version: (Trial Edition)

=== Xamarin.Android ===

Version: 4.18.0 (Trial Edition)
Android SDK: /Users/jatin66/Desktop/Backup/android-sdk-macosx
	Supported Android versions:
		1.6   (API level 4)
		2.1   (API level 7)
		2.2   (API level 8)
		2.3   (API level 10)
		3.0   (API level 11)
		3.1   (API level 12)
		3.2   (API level 13)
		4.0   (API level 14)
		4.0.3 (API level 15)
		4.1   (API level 16)
		4.2   (API level 17)
		4.3   (API level 18)
		4.4   (API level 19)
Java SDK: /usr
java version "1.7.0_65"
Java(TM) SE Runtime Environment (build 1.7.0_65-b17)
Java HotSpot(TM) 64-Bit Server VM (build 24.65-b04, mixed mode)

=== Xamarin.iOS ===

Version: (Trial Edition)
Hash: 08968c4
Build date: 2014-10-20 21:48:06-0400

=== Build Information ===

Release ID: 505030006
Git revision: fbe3e9453daf6a3bb9a9709ed22bec35f7c9056b
Build date: 2014-10-23 13:08:38-04
Xamarin addins: e44add2b39de4dd57c0742bb2e620dfad84c64c6

=== Operating System ===

Mac OS X 10.10.0
Darwin Jatin66s-iMac.local 14.0.0 Darwin Kernel Version 14.0.0
    Fri Sep 19 00:26:44 PDT 2014
    root:xnu-2782.1.97~2/RELEASE_X86_64 x86_64
Comment 2 Rolf Bjarne Kvinge [MSFT] 2014-11-05 02:55:47 UTC
This is not relative to AOT, it depends on the registrar. For iOS device builds, we default to a static registrar that shows the errors at build time (it builds slower, but runs faster), and on iOS simulator builds, we default to a dynamic registrar that shows the errors at runtime.

For Mac builds we currently always default to the dynamic registrar, so you'll get the errors at runtime. You can however select the static registrar by adding "--registrar:static" to the additional mmp arguments in the project's 'Mac Build' options.