Bug 29727 - Assertion at sgen-stw.c:68, condition `info->stack_start >= info->stack_start_limit && info->stack_start < info->stack_end' not met
Summary: Assertion at sgen-stw.c:68, condition `info->stack_start >= info->stack_start...
Alias: None
Product: iOS
Classification: Xamarin
Component: XI runtime ()
Version: XI 8.9.x (iOS 8.3)
Hardware: PC Mac OS
: Normal normal
Target Milestone: Untriaged
Assignee: Mark Probst
Depends on:
Reported: 2015-05-04 21:07 UTC by Frank A. Krueger
Modified: 2016-06-09 00:16 UTC (History)
4 users (show)

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

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Description Frank A. Krueger 2015-05-04 21:07:48 UTC
I get this spurious error. It doesn't happen often, but it looks pretty nasty. Running on a 6 Plus.

The cctor is implicit:

namespace SpaceTrade
	public static partial class NameMatrices
		public static readonly SparseMatrix LastNames = new SparseMatrix (new SparseValue[][] {
			new SparseValue[] { new SparseValue (1, 2433), ... },
			new SparseValue[] { new SparseValue (29, 537), ... },


using System;

namespace SpaceTrade
	public struct SparseValue
		public ushort C;
		public ushort V;
		public SparseValue (ushort c, ushort v)
			C = c;
			V = v;

	public class SparseMatrix
		readonly SparseValue[][] rows;
		public SparseMatrix (SparseValue[][] rows)
			this.rows = rows;
		public ushort this[int row, int col] {
			get {
				var r = rows [row];
				for (var i = 0; i < r.Length; i++) {
					if (r [i].C == col)
						return r [i].V;
				return 0;

error: * Assertion at ../../../../../mono/mono/metadata/sgen-stw.c:68, condition `info->stack_start >= info->stack_start_limit && info->stack_start < info->stack_end' not met
critical: Stacktrace:
critical:   at <unknown> <0xffffffff>
critical:   at (wrapper managed-to-native) object.__icall_wrapper_mono_array_new_specific (intptr,int) <0xffffffff>
critical:   at SpaceTrade.NameMatrices..cctor () [0x00000] in /Users/fak/Dropbox/Projects/SpaceTrade/SpaceTrade.Shared/LastNames.cs:7
critical:   at (wrapper runtime-invoke) object.runtime_invoke_dynamic (intptr,intptr,intptr,intptr) <0xffffffff>
critical:   at <unknown> <0xffffffff>
critical:   at SpaceTrade.Game.Genesis () [0x00058] in /Users/fak/Dropbox/Projects/SpaceTrade/SpaceTrade.Shared/Genesis.cs:516
critical:   at SpaceTrade.Game..ctor (string,bool) [0x0009c] in /Users/fak/Dropbox/Projects/SpaceTrade/SpaceTrade.Shared/Game.cs:160
critical:   at SpaceTrade.Game.New () [0x00026] in /Users/fak/Dropbox/Projects/SpaceTrade/SpaceTrade.Shared/Game.cs:674
critical:   at SpaceTrade.WatchExt.TitleController.HandleNewGame () [0x00001] in /Users/fak/Dropbox/Projects/SpaceTrade/SpaceTrade/TitleController.cs:34
critical:   at (wrapper runtime-invoke) object.runtime_invoke_dynamic (intptr,intptr,intptr,intptr) <0xffffffff>
critical:   at <unknown> <0xffffffff>
critical:   at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain (int,string[],intptr,intptr) <0xffffffff>
critical:   at UIKit.UIApplication.Main (string[],intptr,intptr) [0x00005] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:62
critical:   at UIKit.UIApplication.Main (string[],string,string) [0x0001c] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:45
critical:   at SpaceTrade.Application.Main (string[]) [0x00008] in /Users/fak/Dropbox/Projects/SpaceTrade/SpaceTrade/Main.cs:17
critical:   at (wrapper runtime-invoke) object.runtime_invoke_dynamic (intptr,intptr,intptr,intptr) <0xffffffff>

=== Xamarin Studio ===

Version 5.8.3 (build 1)
Installation UUID: e51e2705-c52a-4ae8-aa07-c481d6ab8a7a
	Mono 3.12.1 ((detached/0849ec7)
	GTK+ 2.24.23 (Raleigh theme)

	Package version: 312010003

=== Xamarin.Android ===

Version: (Enterprise Edition)
Android SDK: /Users/fak/Library/Developer/Xamarin/android-sdk-mac_x86
	Supported Android versions:
		2.1   (API level 7)
		2.2   (API level 8)
		2.3   (API level 10)
		3.1   (API level 12)
		4.0   (API level 14)
		4.0.3 (API level 15)
		4.4   (API level 19)
		5.0   (API level 21)
Java SDK: /usr
java version "1.7.0_51"
Java(TM) SE Runtime Environment (build 1.7.0_51-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.51-b03, mixed mode)

=== Xamarin Android Player ===

Version: Unknown version
Location: /Applications/Xamarin Android Player.app

=== Apple Developer Tools ===

Xcode 6.3.1 (7703)
Build 6D1002

=== Xamarin.iOS ===

Version: (Enterprise Edition)
Hash: f7736a4
Build date: 2015-04-09 04:22:08-0400

=== Xamarin.Mac ===

Version: (Enterprise Edition)

=== Build Information ===

Release ID: 508030001
Git revision: 6e8e725e0d689351901c2c70453bfa4ea25e293b
Build date: 2015-04-06 20:31:47-04
Xamarin addins: 051cd5f8c1b5dbfc87eaef80a74aec03f34c60a8

=== Operating System ===

Mac OS X 10.10.3
Darwin lepton.local 14.3.0 Darwin Kernel Version 14.3.0
    Mon Mar 23 11:59:05 PDT 2015
    root:xnu-2782.20.48~5/RELEASE_X86_64 x86_64
Comment 1 Mark Probst 2015-05-05 13:32:02 UTC
This looks very much like the bug I fixed in 23372959cfe004fb1d47d25307871ece82c3f396.  Could you test with a recent mono?
Comment 3 Sebastien Pouliot 2016-06-09 00:16:14 UTC
We have not received the requested information. If you are still experiencing this issue please provide all the requested information and re-open the bug report. Thanks!