SIGSEGV while executing native code when initWithFormat:arguments: when building for 64 bit

[LGFox]

This code causes app crash on 'iPhone 7 Plus iOS 10.3' simulator with x64 build:

var testString = NSStringUtility.LocalizedFormat(NSBundle.MainBundle.LocalizedNSString("cb_reminders_detail_repeat_untiloccurrences"), 110, 1.508, 10);

It seems, it relates to this bug
Stacktrace:

2017-08-14 20:22:34.310 App.iOS[86905:5189452] critical: Stacktrace:

2017-08-14 20:22:34.311 App.iOS[86905:5189452] critical: at <0xffffffff>
2017-08-14 20:22:34.311 App.iOS[86905:5189452] critical: at (wrapper managed-to-native) App.iOS.Classes.LocalizationUtility.NSStringUtility.NSStringInitWithFormatArguments (intptr,intptr,intptr,intptr) [0x0000c] in <316d4c67b02147a5bd23e98bd7553ede>:0
2017-08-14 20:22:34.312 App.iOS[86905:5189452] critical: at App.iOS.Classes.LocalizationUtility.NSStringUtility.LocalizedFormat (Foundation.NSString,App.iOS.Classes.LocalizationUtility.VariadicArguments.VariadicArgument[]) [0x00046] in F:\Git\CB.MobileIOS\App.iOS\Classes\LocalizationUtility\NSStringUtility.cs:40
2017-08-14 20:22:34.312 App.iOS[86905:5189452] critical: at App.iOS.Pages.SignIn.SignInViewController.CreateKeepMeSignView () [0x00061] in F:\Git\CB.MobileIOS\App.iOS\Pages\SignIn\SignInViewController.cs:154
2017-08-14 20:22:34.312 App.iOS[86905:5189452] critical: at App.iOS.Pages.SignIn.SignInViewController.CreateMarkUp () [0x00154] in F:\Git\CB.MobileIOS\App.iOS\Pages\SignIn\SignInViewController.cs:107
2017-08-14 20:22:34.313 App.iOS[86905:5189452] critical: at App.iOS.Pages.SignIn.SignInViewController.OnViewDidLoad () [0x00008] in F:\Git\CB.MobileIOS\App.iOS\Pages\SignIn\SignInViewController.cs:55
2017-08-14 20:22:34.313 App.iOS[86905:5189452] critical: at BusinessLogic.Classes.CatchExceptionHelper.CatchException (System.Action) [0x00002] in F:\Git\CB.MobileIOS\Libraries\BusinessLogic\Classes\CatchExceptionHelper.cs:23
2017-08-14 20:22:34.314 App.iOS[86905:5189452] critical: at App.iOS.Pages.ABaseViewController`2<TParameter_REF, TData_REF>.ViewDidLoad () [0x0000f] in F:\Git\CB.MobileIOS\App.iOS\Pages\ABaseViewController.cs:133
2017-08-14 20:22:34.314 App.iOS[86905:5189452] critical: at (wrapper runtime-invoke) object.runtime_invoke_void__this__ (object,intptr,intptr,intptr) [0x0004f] in <2f4074c3120b4d80802e10af84b67d41>:0
2017-08-14 20:22:34.314 App.iOS[86905:5189452] critical: at <0xffffffff>
2017-08-14 20:22:34.315 App.iOS[86905:5189452] critical: at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain (int,string[],intptr,intptr) [0x0005c] in <58a9bd8a3cbb4d0092bc0a767ff66c0f>:0
2017-08-14 20:22:34.316 App.iOS[86905:5189452] critical: at UIKit.UIApplication.Main (string[],intptr,intptr) [0x00005] in /Users/builder/data/lanes/4691/d2270eec/source/xamarin-macios/src/UIKit/UIApplication.cs:79
2017-08-14 20:22:34.317 App.iOS[86905:5189452] critical: at UIKit.UIApplication.Main (string[],string,string) [0x00038] in /Users/builder/data/lanes/4691/d2270eec/source/xamarin-macios/src/UIKit/UIApplication.cs:63
2017-08-14 20:22:34.317 App.iOS[86905:5189452] critical: at App.iOS.Application.Main (string[]) [0x00336] in F:\Git\CB.MobileIOS\App.iOS\Main.cs:121
2017-08-14 20:22:34.317 App.iOS[86905:5189452] critical: at (wrapper runtime-invoke) .runtime_invoke_void_object (object,intptr,intptr,intptr) [0x00051] in <316d4c67b02147a5bd23e98bd7553ede>:0
2017-08-14 20:22:34.318 App.iOS[86905:5189452] critical:
Native stacktrace:
2017-08-14 20:22:34.334 App.iOS[86905:5189452] critical: 0 App.iOS 0x000000010223f2b1 mono_handle_native_crash + 257
2017-08-14 20:22:34.335 App.iOS[86905:5189452] critical: 1 App.iOS 0x000000010224c380 mono_sigsegv_signal_handler + 288
2017-08-14 20:22:34.335 App.iOS[86905:5189452] critical: 2 libsystem_platform.dylib 0x000000010f340bba _sigtramp + 26
2017-08-14 20:22:34.335 App.iOS[86905:5189452] critical: 3 ??? 0x0000000000000000 0x0 + 0
2017-08-14 20:22:34.336 App.iOS[86905:5189452] critical: 4 CoreFoundation 0x000000010da77d83 _CFStringCreateWithFormatAndArgumentsAux2 + 243
2017-08-14 20:22:34.336 App.iOS[86905:5189452] critical: 5 App.iOS 0x0000000102411009 xamarin_dyn_objc_msgSend + 217
2017-08-14 20:22:34.336 App.iOS[86905:5189452] critical: 6 ??? 0x000000012983b528 0x0 + 4991464744
2017-08-14 20:22:34.337 App.iOS[86905:5189452] critical:
=================================================================
Got a SIGSEGV while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.
=================================================================

[rubo]

This is a known issue. Sadly, I don't know any workarounds for this. The simplest way is to go with 32-bit apps on simulators. Not the best solution, of course, but we have what we have.

Xamarin team is aware of the issue but seems they put it on hold due to the fact it's pretty heavy to fix. I believe the importance of this issue is underrated and it needs more votes on their issue tracker to catch their attention.

[LGFox]

At least, it works on real devices.

[rubo]

Made a small improvement in 9d699b1 to prevent crashing on 64-bit simulators. Instead, it now returns the key itself. Definitely, much better than crashing.