[Bug] MAUI templates crashing on iOS (Foundation.NSMutableData:AppendBytes)

[PureWeen]

Description

Application is failing to start

=================================================================
	Managed Stacktrace:
=================================================================
	  at <unknown> <0xffffffff>
	  at ObjCRuntime.Messaging:void_objc_msgSend_IntPtr_UIntPtr <0x0006e>
	  at Foundation.NSMutableData:AppendBytes <0x0004a>
	  at Foundation.NSData:FromStream <0x000dc>
	  at Microsoft.Maui.EmbeddedFontLoader:LoadFont <0x0006a>
	  at Microsoft.Maui.FontRegistrar:LoadEmbeddedFont <0x000a0>
	  at Microsoft.Maui.FontRegistrar:LoadNativeAppFont <0x0003a>
	  at Microsoft.Maui.FontRegistrar:GetFont <0x0011a>
	  at Microsoft.Maui.FontManager:CleanseFontName <0x00022>
	  at Microsoft.Maui.FontManager:CreateFont <0x0015e>
	  at System.Collections.Concurrent.ConcurrentDictionary`2:GetOrAdd <0x000e2>
	  at Microsoft.Maui.FontManager:GetFont <0x00074>
	  at Microsoft.Maui.FontManager:GetFont <0x00032>
	  at Microsoft.Maui.LabelExtensions:UpdateFont <0x0002a>
	  at Microsoft.Maui.LabelExtensions:UpdateFont <0x0001c>
	  at Microsoft.Maui.Handlers.LabelHandler:MapFont <0x0003e>
	  at Microsoft.Maui.Controls.Label:MapFont <0x0002e>
	  at <>c__DisplayClass5_0:<Add>b__0 <0x00048>
	  at Microsoft.Maui.PropertyMapper:UpdatePropertyCore <0x00036>
	  at Microsoft.Maui.PropertyMapper:UpdateProperties <0x0005e>

Steps to Reproduce

• Install the latest main bits https://github.com/dotnet/maui/blob/main/.github/DEVELOPMENT.md

dotnet workload install maui `
   --from-rollback-file https://aka.ms/dotnet/maui/preview.10.json `
   --source https://aka.ms/dotnet6/nuget/index.json `
   --source https://api.nuget.org/v3/index.json

• dotnet new maui
• launch the iOS app

Expected Behavior

doesn't crash

Actual Behavior

crashes

Basic Information

• Version with issue: main
• Last known good version: p10

This is acting like an issue with the iOS workloads. If you change the version of MAUI to be p.10 but still use the p.11 iOS workloads the app still crashes.

[mattleibow]

This feels like a bug in iOS since we are using the same code in maui - the only difference is the ios/runtime version.

[rolfbjarne]

p.11 iOS workloads

The p11 iOS workload contains breaking changes that may very well cause this (the last version doesn't work for other reasons).

If you attach a binlog, I can see exactly which version you built with, and check if it's a breaking change or a bug.

[PureWeen]

@rolfbjarne
msbuild.binlog.zip

[rolfbjarne]

This seems to be an interpreter bug. If I disable the interpreter, the sample works.

The crash occurs in [NSConcreteMutableData appendBytes:length:], and a bit of debugging in lldb reveals that the length argument is incorrect:

(lldb) bt
* thread dotnet/maui#1, name = 'tid_103', queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
  * frame #0: 0x00000001142d81bd Foundation`-[NSConcreteMutableData appendBytes:length:]
    frame dotnet/maui#1: 0x000000010cb0b719 libxamarin-dotnet-debug.dylib`xamarin_dyn_objc_msgSend at trampolines-x86_64-objc_msgSend.s:15
    frame dotnet/maui#2: 0x000000010d6e9aed libmonosgen-2.0.dylib`do_icall + 333
    frame dotnet/maui#3: 0x000000010d6e8a7d libmonosgen-2.0.dylib`do_icall_wrapper + 253
    [...]
(lldb) p/x $rcx
(unsigned long) $1 = 0x0000000155738648
(lldb) x/x $rcx
0x155738648: 0x00008000

The length is supposed to be 32768 (0x8000), but instead it's a pointer to that value.

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[rolfbjarne]

CC @akoeplinger @steveisok

This is breaking the default MAUI template, so it's a rather high priority.

It's rather obnoxious to reproduce, because of other breaking changes in later commits that hides this problem, but I believe it should be possible by installing .NET 6 (RTM), and then this package: https://bosstoragemirror.blob.core.windows.net/wrench/main/40db84a71e10a549cdcd3dab746120dba3f84554/5378878/package/notarized/Microsoft.iOS.Bundle.15.0.101-preview.11.279.pkg

[steveisok]

/cc @BrzVlad

Tagging subscribers to this area: @BrzVlad
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

Application is failing to start

=================================================================
	Managed Stacktrace:
=================================================================
	  at <unknown> <0xffffffff>
	  at ObjCRuntime.Messaging:void_objc_msgSend_IntPtr_UIntPtr <0x0006e>
	  at Foundation.NSMutableData:AppendBytes <0x0004a>
	  at Foundation.NSData:FromStream <0x000dc>
	  at Microsoft.Maui.EmbeddedFontLoader:LoadFont <0x0006a>
	  at Microsoft.Maui.FontRegistrar:LoadEmbeddedFont <0x000a0>
	  at Microsoft.Maui.FontRegistrar:LoadNativeAppFont <0x0003a>
	  at Microsoft.Maui.FontRegistrar:GetFont <0x0011a>
	  at Microsoft.Maui.FontManager:CleanseFontName <0x00022>
	  at Microsoft.Maui.FontManager:CreateFont <0x0015e>
	  at System.Collections.Concurrent.ConcurrentDictionary`2:GetOrAdd <0x000e2>
	  at Microsoft.Maui.FontManager:GetFont <0x00074>
	  at Microsoft.Maui.FontManager:GetFont <0x00032>
	  at Microsoft.Maui.LabelExtensions:UpdateFont <0x0002a>
	  at Microsoft.Maui.LabelExtensions:UpdateFont <0x0001c>
	  at Microsoft.Maui.Handlers.LabelHandler:MapFont <0x0003e>
	  at Microsoft.Maui.Controls.Label:MapFont <0x0002e>
	  at <>c__DisplayClass5_0:<Add>b__0 <0x00048>
	  at Microsoft.Maui.PropertyMapper:UpdatePropertyCore <0x00036>
	  at Microsoft.Maui.PropertyMapper:UpdateProperties <0x0005e>

Steps to Reproduce

• Install the latest main bits https://github.com/dotnet/maui/blob/main/.github/DEVELOPMENT.md

 dotnet workload install maui `
   --from-rollback-file https://aka.ms/dotnet/maui/main.json `
   --source https://aka.ms/dotnet6/nuget/index.json `
   --source https://pkgs.dev.azure.com/dnceng/public/_packaging/darc-pub-dotnet-runtime-6f411658/nuget/v3/index.json `
   --source https://pkgs.dev.azure.com/dnceng/public/_packaging/darc-pub-dotnet-emsdk-1ec2e17f/nuget/v3/index.json

• dotnet new maui
• launch the iOS app

Expected Behavior

doesn't crash

Actual Behavior

crashes

Basic Information

• Version with issue: main
• Last known good version: p10

This is acting like an issue with the iOS workloads. If you change the version of MAUI to be p.10 but still use the p.11 iOS workloads the app still crashes.

Author:	PureWeen
Assignees:	-
Labels:	untriaged, area-Codegen-Interpreter-mono, os-ios
Milestone:	-