Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

TypeLoadException thrown for recursive type that .NET allows #15760

Closed
UnityAlex opened this issue Jul 19, 2019 · 6 comments · Fixed by #15761 or Unity-Technologies/mono#1211
Closed

TypeLoadException thrown for recursive type that .NET allows #15760

UnityAlex opened this issue Jul 19, 2019 · 6 comments · Fixed by #15761 or Unity-Technologies/mono#1211
Assignees

Comments

@UnityAlex
Copy link
Contributor

@UnityAlex UnityAlex commented Jul 19, 2019

When running an executable that uses recursively defined types a TypeLoadException is thrown by mono where .NET does not.

Steps to Reproduce

  1. Compile and run the sample code. No additional arguments required.
  2. Observe exception thrown.
using System;

namespace TestRecursiveType
{
    class Program
    {
        static void Main(string[] args)
        {
            SubClass subC = new SubClass();
            Console.WriteLine(subC.GetTest());
        }
    }

    public struct ValueTest<T>
    {
        public readonly T value;
    }

    public abstract class BaseClass<T> where T : BaseClass<T>
    {
        public ValueTest<T> valueTest = default(ValueTest<T>);
    }

    public class SubClass : BaseClass<SubClass>
    {
        private String test = "test";


        public string GetTest()
        {
            return test;
        }
    }
}

Current Behavior


Unhandled Exception:
System.TypeLoadException: Could not set up parent class, due to: Generic Type Definition failed to init, due to: Recursive type definition detected TestRecursiveType.BaseClass`1 assembly:C:\Users\alexthibodeau\source\repos\TestRecursiveType\TestRecursiveType\Program.exe type:BaseClass`1 member:(null) assembly:C:\Users\alexthibodeau\source\repos\TestRecursiveType\TestRecursiveType\Program.exe type:BaseClass`1 member:(null)
[ERROR] FATAL UNHANDLED EXCEPTION: System.TypeLoadException: Could not set up parent class, due to: Generic Type Definition failed to init, due to: Recursive type definition detected TestRecursiveType.BaseClass`1 assembly:C:\Users\alexthibodeau\source\repos\TestRecursiveType\TestRecursiveType\Program.exe type:BaseClass`1 member:(null) assembly:C:\Users\alexthibodeau\source\repos\TestRecursiveType\TestRecursiveType\Program.exe type:BaseClass`1 member:(null)

Expected Behavior

Expecting "test" to be written to console with no exceptions thrown.

On which platforms did you notice this

[ ] macOS
[ ] Linux
[X ] Windows

Version Used:

Mono JIT compiler version 6.5.0 (Visual Studio built mono)
Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors. www.mono-project.com
        TLS:           __thread
        SIGSEGV:       normal
        Notification:  Thread + polling
        Architecture:  amd64
        Disabled:      none
        Misc:          softdebug
        Interpreter:   yes
        LLVM:          supported, not enabled.
        Suspend:       preemptive
        GC:            sgen (concurrent by default)```

@filipnavara

This comment has been minimized.

Copy link
Collaborator

@filipnavara filipnavara commented Jul 19, 2019

This sounds suspiciously similar to a CoreCLR bug (dotnet/coreclr#7957) that was reported years ago and is still not fixed.

@lambdageek

This comment has been minimized.

Copy link
Member

@lambdageek lambdageek commented Jul 19, 2019

There are a lot of edge cases to initialization of recursive class definitions. The CoreCLR one sounds trickier - struct layout seems like it need to know more about the type. Generic constraints shouldn't need a fully initialized class...

@filipnavara

This comment has been minimized.

Copy link
Collaborator

@filipnavara filipnavara commented Jul 19, 2019

This one also involves struct layout through ValueTest<T>, or am I missing something?

Recursive constraints alone work just fine on Mono. We use it in production and regularly test it with up-to-date Mono from git master.

@lambdageek

This comment has been minimized.

Copy link
Member

@lambdageek lambdageek commented Jul 19, 2019

oh I missed that. you're right

@lambdageek

This comment has been minimized.

Copy link
Member

@lambdageek lambdageek commented Jul 19, 2019

Stack trace to the point where mono hits "Recursive type definition detected"

* thread #1, name = 'tid_307', queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
  * frame #0: 0x000000010019e987 mono`mono_class_init_internal(klass=0x0000000101004808) at class-init.c:4322 [opt]
    frame #1: 0x000000010019e60c mono`mono_class_setup_fields(klass=0x0000000102812708) at class-init.c:275 [opt]
    frame #2: 0x000000010019f32c mono`mono_class_layout_fields(klass=<unavailable>, base_instance_size=<unavailable>, packing_size=0, explicit_size=0, sre=0) at class-init.c:3619 [opt]
    frame #3: 0x000000010019e8e5 mono`mono_class_setup_fields(klass=0x0000000102800c28) at class-init.c:358 [opt]
    frame #4: 0x00000001001a6a2c mono`type_has_references [inlined] mono_class_init_sizes(klass=<unavailable>) at class-init.c:3473 [opt]
    frame #5: 0x00000001001a6a06 mono`type_has_references [inlined] class_has_references(klass=<unavailable>) at class-init.c:3480 [opt]
    frame #6: 0x00000001001a6a06 mono`type_has_references(klass=<unavailable>, ftype=0x00000001028125a8) at class-init.c:3493 [opt]
    frame #7: 0x000000010019f45a mono`mono_class_layout_fields(klass=<unavailable>, base_instance_size=<unavailable>, packing_size=0, explicit_size=0, sre=0) at class-init.c:3653 [opt]
    frame #8: 0x000000010019e8e5 mono`mono_class_setup_fields(klass=0x0000000101004808) at class-init.c:358 [opt]
    frame #9: 0x000000010019ead4 mono`mono_class_init_internal(klass=0x0000000101004808) at class-init.c:4374 [opt]
    frame #10: 0x000000010019ea73 mono`mono_class_init_internal(klass=0x0000000102017e00) at class-init.c:4359 [opt]
    frame #11: 0x000000010019eab3 mono`mono_class_init_internal(klass=0x0000000101004708) at class-init.c:4369 [opt]
    frame #12: 0x00000001000297cb mono`mono_method_to_ir(cfg=<unavailable>, method=0x0000000101000d58, start_bblock=0x0000000102015f68, end_bblock=0x00000001020160a8, return_var=0x0000000000000000, inline_args=0x0000000000000000, inline_offset=0, is_virtual_call=0) at method-to-ir.c:8517 [opt]
    frame #13: 0x0000000100005e44 mono`mini_method_compile(method=<unavailable>, opts=374434303, domain=0x0000000101206160, flags=JIT_FLAG_RUN_CCTORS, parts=0, aot_method_index=-1) at mini.c:3437 [opt]
    frame #14: 0x0000000100008f9c mono`mono_jit_compile_method_inner(method=0x0000000101000d58, target_domain=0x0000000101206160, opt=<unavailable>, error=0x00007ffeefbff2a8) at mini.c:4025 [opt]
    frame #15: 0x000000010000ce12 mono`mono_jit_compile_method_with_opt(method=0x0000000101000d58, opt=374434303, jit_only=1, error=<unavailable>) at mini-runtime.c:2434 [opt]
    frame #16: 0x0000000100010f4d mono`mono_jit_runtime_invoke [inlined] mono_jit_compile_method_jit_only(method=<unavailable>, error=<unavailable>) at mini-runtime.c:2498 [opt]
    frame #17: 0x0000000100010f29 mono`mono_jit_runtime_invoke(method=<unavailable>, obj=<unavailable>, params=0x00007ffeefbff268, exc=0x0000000000000000, error=<unavailable>) at mini-runtime.c:3043 [opt]
    frame #18: 0x0000000100222c68 mono`mono_runtime_invoke_checked [inlined] do_runtime_invoke(method=0x0000000101000d58, obj=0x0000000000000000, params=0x00007ffeefbff268, exc=<unavailable>, error=0x00007ffeefbff2a8) at object.c:3016 [opt]
    frame #19: 0x0000000100222c32 mono`mono_runtime_invoke_checked(method=0x0000000101000d58, obj=0x0000000000000000, params=0x00007ffeefbff268, error=0x00007ffeefbff2a8) at object.c:3184 [opt]
    frame #20: 0x000000010022a12e mono`mono_runtime_exec_main_checked at object.c:5118 [opt]
    frame #21: 0x000000010022a0fa mono`mono_runtime_exec_main_checked(method=0x0000000101000d58, args=<unavailable>, error=0x00007ffeefbff2a8) at object.c:5221 [opt]
    frame #22: 0x000000010006e88d mono`mono_jit_exec at driver.c:1322 [opt]
    frame #23: 0x000000010006e87f mono`mono_jit_exec(domain=<unavailable>, assembly=<unavailable>, argc=1, argv=0x00007ffeefbff628) at driver.c:1267 [opt]
    frame #24: 0x00000001000718fb mono`mono_main [inlined] main_thread_handler at driver.c:1404 [opt]
    frame #25: 0x00000001000718c1 mono`mono_main(argc=2, argv=<unavailable>) at driver.c:2623 [opt]
    frame #26: 0x00000001000015ea mono`main [inlined] mono_main_with_options(argc=<unavailable>, argv=<unavailable>) at main.c:50 [opt]
    frame #27: 0x00000001000015d6 mono`main(argc=2, argv=<unavailable>) at main.c:410 [opt]
    frame #28: 0x00007fff7d8bf3d5 libdyld.dylib`start + 1

The klass in frame 11 is TestRecursiveType.SubClass.
In frame 10 klass is TestRecursiveType.BaseClass`1[TestRecursiveType.SubClass]
In frame 9 klass is TestRecursiveType.BaseClass`1[T]
In frame 3 klass is TestRecursiveType.ValueTest`1[T]
In frame 1 klass is T (owned by BaseClass`1[T])

@lambdageek lambdageek self-assigned this Jul 19, 2019
lambdageek added a commit to lambdageek/mono that referenced this issue Jul 19, 2019
…raint

aren't blittlable.

Don't try to layout the field to find out if it's blittable.

Fixes certain recursive examples.

```
using System;

namespace TestRecursiveType
{
    class Program
    {
        static void Main(string[] args)
        {
            SubClass subC = new SubClass();
            Console.WriteLine(subC.GetTest());
        }
    }

    public struct ValueTest<U>
    {
        // When U is instantiated with T, from BaseClass, we know it'll be a
	// reference field, so we know the instantiation ValueTest<T> won't
	// be blittable.
        public readonly U value;
    }

    public abstract class BaseClass<T> where T : BaseClass<T>
    {
        public ValueTest<T> valueTest = default(ValueTest<T>);
    }

    public class SubClass : BaseClass<SubClass>
    {
        private String test = "test";

        public string GetTest()
        {
            return test;
        }
    }
}
```

Fixes mono#15760
lambdageek added a commit to lambdageek/mono that referenced this issue Jul 19, 2019
…raint

aren't blittlable.

Don't try to layout the field to find out if it's blittable.

Fixes certain recursive examples.

```
using System;

namespace TestRecursiveType
{
    class Program
    {
        static void Main(string[] args)
        {
            SubClass subC = new SubClass();
            Console.WriteLine(subC.GetTest());
        }
    }

    public struct ValueTest<U>
    {
        // When U is instantiated with T, from BaseClass, we know it'll be a
	// reference field, so we know the instantiation ValueTest<T> won't
	// be blittable.
        public readonly U value;
    }

    public abstract class BaseClass<T> where T : BaseClass<T>
    {
        public ValueTest<T> valueTest = default(ValueTest<T>);
    }

    public class SubClass : BaseClass<SubClass>
    {
        private String test = "test";

        public string GetTest()
        {
            return test;
        }
    }
}
```

Fixes mono#15760
lambdageek added a commit that referenced this issue Jul 25, 2019
…raint aren't blittlable. (#15761)

* [metadata] Fields whose types are gparams with a reference type constraint
aren't blittlable.
Don't try to layout the field to find out if it's blittable.
For gshared gparams, follow the blittability of the constraint.

Fixes certain recursive examples.

```
using System;

namespace TestRecursiveType
{
    class Program
    {
        static void Main(string[] args)
        {
            SubClass subC = new SubClass();
            Console.WriteLine(subC.GetTest());
        }
    }

    public struct ValueTest<U>
    {
        // When U is instantiated with T, from BaseClass, we know it'll be a
	// reference field, so we know the instantiation ValueTest<T> won't
	// be blittable.
        public readonly U value;
    }

    public abstract class BaseClass<T> where T : BaseClass<T>
    {
        public ValueTest<T> valueTest = default(ValueTest<T>);
    }

    public class SubClass : BaseClass<SubClass>
    {
        private String test = "test";

        public string GetTest()
        {
            return test;
        }
    }
}
```

Fixes #15760

---

The failure is happening when we are doing mono_class_setup_fields ("BaseClass<T>") which needs to decide for each field whether it is blittable or not. So therefore we are trying to decide if ValueTest<T> (that is: the ValueTest<U> field inside BaseClass<T>) is blittable or not.

So we instantiate U with T.
Now to decide whether VaueTest<T> is blittable or not, we look at every field.
So then we look at T value.
To decide if T is blittable we first check if it's a reference type.

That check is currently inadequate for generic parameters - what the PR adds is the ability to see if theres a T : class constraint or a T : C constraint - where C is some class. As soon as we know that T's constraint will force it to be a reference type we can definitely say that T won't be blittable without having to initialize C, at all.

Previously, Mono would see that T is some kind of type for which it couldn't definitively decide that it's a reference type and it would call: mono_class_setup_fields (field_class) which would then try to setup the fields of the parent class BaseClass<T>. And that would hit the recursion check.
UnityAlex added a commit to Unity-Technologies/mono that referenced this issue Jul 30, 2019
…raint aren't blittlable. (mono#15761)

* [metadata] Fields whose types are gparams with a reference type constraint
aren't blittlable.
Don't try to layout the field to find out if it's blittable.
For gshared gparams, follow the blittability of the constraint.

Fixes certain recursive examples.

```
using System;

namespace TestRecursiveType
{
    class Program
    {
        static void Main(string[] args)
        {
            SubClass subC = new SubClass();
            Console.WriteLine(subC.GetTest());
        }
    }

    public struct ValueTest<U>
    {
        // When U is instantiated with T, from BaseClass, we know it'll be a
	// reference field, so we know the instantiation ValueTest<T> won't
	// be blittable.
        public readonly U value;
    }

    public abstract class BaseClass<T> where T : BaseClass<T>
    {
        public ValueTest<T> valueTest = default(ValueTest<T>);
    }

    public class SubClass : BaseClass<SubClass>
    {
        private String test = "test";

        public string GetTest()
        {
            return test;
        }
    }
}
```

Fixes mono#15760

---

The failure is happening when we are doing mono_class_setup_fields ("BaseClass<T>") which needs to decide for each field whether it is blittable or not. So therefore we are trying to decide if ValueTest<T> (that is: the ValueTest<U> field inside BaseClass<T>) is blittable or not.

So we instantiate U with T.
Now to decide whether VaueTest<T> is blittable or not, we look at every field.
So then we look at T value.
To decide if T is blittable we first check if it's a reference type.

That check is currently inadequate for generic parameters - what the PR adds is the ability to see if theres a T : class constraint or a T : C constraint - where C is some class. As soon as we know that T's constraint will force it to be a reference type we can definitely say that T won't be blittable without having to initialize C, at all.

Previously, Mono would see that T is some kind of type for which it couldn't definitively decide that it's a reference type and it would call: mono_class_setup_fields (field_class) which would then try to setup the fields of the parent class BaseClass<T>. And that would hit the recursion check.

Unity cherry-pick note: Needed to bring MONO_CLASS_IS_INTERFACE_INTERNAL
and mono_class_get_valuetype_class forward
jonpryor added a commit to xamarin/xamarin-android that referenced this issue Sep 6, 2019
Changes: http://github.com/mono/mono/compare/2c3aeaf3780de7392a0d3cbe4dcf86846eb4dffa...29b1ac19c961b959a09097dbc0fe4cd567cc5298

	$ git diff --shortstat 2c3aeaf3..29b1ac19
	 1528 files changed, 45421 insertions(+), 21967 deletions(-)

Changes: mono/api-doc-tools@d03e819...5da8127

	$ git diff --shortstat d03e8198..5da8127a
	 1001 files changed, 86168 insertions(+), 11863 deletions(-)

Changes: mono/api-snapshot@e09042d...1ca8e82

	$ git diff --shortstat e09042da..1ca8e82f
        28 files changed, 612 insertions(+), 217 deletions(-)

Changes: mono/cecil@a6c8f5e...cb6c1ca

	$ git diff --shortstat a6c8f5e1..cb6c1ca9
	 13 files changed, 233 insertions(+), 88 deletions(-)

Changes: mono/corefx@4806207...470e0e1

	$ git diff --shortstat 4806207f...470e0e10
	 4 files changed, 31 insertions(+), 12 deletions(-)

Changes: mono/linker@ebe2a1f...1f87de3

	$ git diff --shortstat ebe2a1f4...1f87de35
        90 files changed, 3219 insertions(+), 1224 deletions(-)

Changes: xamarin/java.interop@befdbc0...be6048e

	$ git diff --shortstat befdbc03...be6048ed
        3 files changed, 3 insertions(+), 3 deletions(-)

Upstream-Fixes: https://bugs.winehq.org/show_bug.cgi?id=47561
Upstream-Fixes: https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems/edit/967582
Upstream-Fixes: dotnet/coreclr#25071
Upstream-Fixes: dotnet/coreclr#25242
Upstream-Fixes: dotnet/coreclr#25632
Upstream-Fixes: dotnet/coreclr#25709
Upstream-Fixes: dotnet/corefx#37955
Upstream-Fixes: dotnet/corefx#38455
Upstream-Fixes: mono/mono#7377
Upstream-Fixes: mono/mono#8747
Upstream-Fixes: mono/mono#9621
Upstream-Fixes: mono/mono#9664
Upstream-Fixes: mono/mono#9706
Upstream-Fixes: mono/mono#10201
Upstream-Fixes: mono/mono#10645
Upstream-Fixes: mono/mono#10748
Upstream-Fixes: mono/mono#10848
Upstream-Fixes: mono/mono#12141
Upstream-Fixes: mono/mono#13311
Upstream-Fixes: mono/mono#13408
Upstream-Fixes: mono/mono#13412
Upstream-Fixes: mono/mono#13891
Upstream-Fixes: mono/mono#13923
Upstream-Fixes: mono/mono#13945
Upstream-Fixes: mono/mono#14170
Upstream-Fixes: mono/mono#14214
Upstream-Fixes: mono/mono#14214
Upstream-Fixes: mono/mono#14215
Upstream-Fixes: mono/mono#14243
Upstream-Fixes: mono/mono#14377
Upstream-Fixes: mono/mono#14495
Upstream-Fixes: mono/mono#14555
Upstream-Fixes: mono/mono#14724
Upstream-Fixes: mono/mono#14729
Upstream-Fixes: mono/mono#14772
Upstream-Fixes: mono/mono#14792
Upstream-Fixes: mono/mono#14793
Upstream-Fixes: mono/mono#14809
Upstream-Fixes: mono/mono#14830
Upstream-Fixes: mono/mono#14839
Upstream-Fixes: mono/mono#14841
Upstream-Fixes: mono/mono#14847
Upstream-Fixes: mono/mono#14864
Upstream-Fixes: mono/mono#14871
Upstream-Fixes: mono/mono#14917
Upstream-Fixes: mono/mono#14945
Upstream-Fixes: mono/mono#14946
Upstream-Fixes: mono/mono#14948
Upstream-Fixes: mono/mono#14957
Upstream-Fixes: mono/mono#14959
Upstream-Fixes: mono/mono#14960
Upstream-Fixes: mono/mono#14961
Upstream-Fixes: mono/mono#14963
Upstream-Fixes: mono/mono#14971
Upstream-Fixes: mono/mono#14972
Upstream-Fixes: mono/mono#14975
Upstream-Fixes: mono/mono#15023
Upstream-Fixes: mono/mono#15048
Upstream-Fixes: mono/mono#15058
Upstream-Fixes: mono/mono#15080
Upstream-Fixes: mono/mono#15182
Upstream-Fixes: mono/mono#15188
Upstream-Fixes: mono/mono#15189
Upstream-Fixes: mono/mono#15261
Upstream-Fixes: mono/mono#15262
Upstream-Fixes: mono/mono#15263
Upstream-Fixes: mono/mono#15265
Upstream-Fixes: mono/mono#15268
Upstream-Fixes: mono/mono#15307
Upstream-Fixes: mono/mono#15324
Upstream-Fixes: mono/mono#15329
Upstream-Fixes: mono/mono#15330
Upstream-Fixes: mono/mono#15441
Upstream-Fixes: mono/mono#15446
Upstream-Fixes: mono/mono#15503
Upstream-Fixes: mono/mono#15541
Upstream-Fixes: mono/mono#15551
Upstream-Fixes: mono/mono#15556
Upstream-Fixes: mono/mono#15596
Upstream-Fixes: mono/mono#15691
Upstream-Fixes: mono/mono#15692
Upstream-Fixes: mono/mono#15740
Upstream-Fixes: mono/mono#15751
Upstream-Fixes: mono/mono#15760
Upstream-Fixes: mono/mono#15781
Upstream-Fixes: mono/mono#15794
Upstream-Fixes: mono/mono#15825
Upstream-Fixes: mono/mono#15853
Upstream-Fixes: mono/mono#15878
Upstream-Fixes: mono/mono#15887
Upstream-Fixes: mono/mono#15990
Upstream-Fixes: mono/mono#16032
Upstream-Fixes: mono/mono#16411
Upstream-Fixes: mono/mono#16486
Upstream-Fixes: https://github.com/mono/mono/issues/25709
Upstream-Fixes: https://github.com/mono/mono/issues/38821
Upstream-Fixes: #3112
Upstream-Fixes: #3168

Update `build-tools/automation/build.groovy` so that it fully cleans
the build tree before starting the build, so that the vestigial mono
submodule (removed in 0c9f83b) is *actually* removed from the build
tree, so that we don't inadvertently use *ancient* submodule contents.
jonpryor added a commit to jonpryor/xamarin-android that referenced this issue Sep 6, 2019
Changes: http://github.com/mono/mono/compare/2c3aeaf3780de7392a0d3cbe4dcf86846eb4dffa...29b1ac19c961b959a09097dbc0fe4cd567cc5298

	$ git diff --shortstat 2c3aeaf3..29b1ac19
	 1528 files changed, 45421 insertions(+), 21967 deletions(-)

Changes: mono/api-doc-tools@d03e819...5da8127

	$ git diff --shortstat d03e8198..5da8127a
	 1001 files changed, 86168 insertions(+), 11863 deletions(-)

Changes: mono/api-snapshot@e09042d...1ca8e82

	$ git diff --shortstat e09042da..1ca8e82f
        28 files changed, 612 insertions(+), 217 deletions(-)

Changes: mono/cecil@a6c8f5e...cb6c1ca

	$ git diff --shortstat a6c8f5e1..cb6c1ca9
	 13 files changed, 233 insertions(+), 88 deletions(-)

Changes: mono/corefx@4806207...470e0e1

	$ git diff --shortstat 4806207f...470e0e10
	 4 files changed, 31 insertions(+), 12 deletions(-)

Changes: mono/linker@ebe2a1f...1f87de3

	$ git diff --shortstat ebe2a1f4...1f87de35
	 90 files changed, 3219 insertions(+), 1224 deletions(-)

Changes: xamarin/java.interop@75b1189...4fd3539

	$ git diff --shortstat 75b11891...4fd35393
	 34 files changed, 448 insertions(+), 52 deletions(-)

Upstream-Fixes: https://bugs.winehq.org/show_bug.cgi?id=47561
Upstream-Fixes: https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems/edit/967582
Upstream-Fixes: dotnet/coreclr#25071
Upstream-Fixes: dotnet/coreclr#25242
Upstream-Fixes: dotnet/coreclr#25632
Upstream-Fixes: dotnet/coreclr#25709
Upstream-Fixes: dotnet/corefx#37955
Upstream-Fixes: dotnet/corefx#38455
Upstream-Fixes: mono/mono#7377
Upstream-Fixes: mono/mono#8747
Upstream-Fixes: mono/mono#9621
Upstream-Fixes: mono/mono#9664
Upstream-Fixes: mono/mono#9706
Upstream-Fixes: mono/mono#10201
Upstream-Fixes: mono/mono#10645
Upstream-Fixes: mono/mono#10748
Upstream-Fixes: mono/mono#10848
Upstream-Fixes: mono/mono#12141
Upstream-Fixes: mono/mono#13311
Upstream-Fixes: mono/mono#13408
Upstream-Fixes: mono/mono#13412
Upstream-Fixes: mono/mono#13891
Upstream-Fixes: mono/mono#13923
Upstream-Fixes: mono/mono#13945
Upstream-Fixes: mono/mono#14170
Upstream-Fixes: mono/mono#14214
Upstream-Fixes: mono/mono#14214
Upstream-Fixes: mono/mono#14215
Upstream-Fixes: mono/mono#14243
Upstream-Fixes: mono/mono#14377
Upstream-Fixes: mono/mono#14495
Upstream-Fixes: mono/mono#14555
Upstream-Fixes: mono/mono#14724
Upstream-Fixes: mono/mono#14729
Upstream-Fixes: mono/mono#14772
Upstream-Fixes: mono/mono#14792
Upstream-Fixes: mono/mono#14793
Upstream-Fixes: mono/mono#14809
Upstream-Fixes: mono/mono#14830
Upstream-Fixes: mono/mono#14839
Upstream-Fixes: mono/mono#14841
Upstream-Fixes: mono/mono#14847
Upstream-Fixes: mono/mono#14864
Upstream-Fixes: mono/mono#14871
Upstream-Fixes: mono/mono#14917
Upstream-Fixes: mono/mono#14945
Upstream-Fixes: mono/mono#14946
Upstream-Fixes: mono/mono#14948
Upstream-Fixes: mono/mono#14957
Upstream-Fixes: mono/mono#14959
Upstream-Fixes: mono/mono#14960
Upstream-Fixes: mono/mono#14961
Upstream-Fixes: mono/mono#14963
Upstream-Fixes: mono/mono#14971
Upstream-Fixes: mono/mono#14972
Upstream-Fixes: mono/mono#14975
Upstream-Fixes: mono/mono#15023
Upstream-Fixes: mono/mono#15048
Upstream-Fixes: mono/mono#15058
Upstream-Fixes: mono/mono#15080
Upstream-Fixes: mono/mono#15182
Upstream-Fixes: mono/mono#15188
Upstream-Fixes: mono/mono#15189
Upstream-Fixes: mono/mono#15261
Upstream-Fixes: mono/mono#15262
Upstream-Fixes: mono/mono#15263
Upstream-Fixes: mono/mono#15265
Upstream-Fixes: mono/mono#15268
Upstream-Fixes: mono/mono#15307
Upstream-Fixes: mono/mono#15324
Upstream-Fixes: mono/mono#15329
Upstream-Fixes: mono/mono#15330
Upstream-Fixes: mono/mono#15441
Upstream-Fixes: mono/mono#15446
Upstream-Fixes: mono/mono#15503
Upstream-Fixes: mono/mono#15541
Upstream-Fixes: mono/mono#15551
Upstream-Fixes: mono/mono#15556
Upstream-Fixes: mono/mono#15596
Upstream-Fixes: mono/mono#15691
Upstream-Fixes: mono/mono#15692
Upstream-Fixes: mono/mono#15740
Upstream-Fixes: mono/mono#15751
Upstream-Fixes: mono/mono#15760
Upstream-Fixes: mono/mono#15781
Upstream-Fixes: mono/mono#15794
Upstream-Fixes: mono/mono#15825
Upstream-Fixes: mono/mono#15853
Upstream-Fixes: mono/mono#15878
Upstream-Fixes: mono/mono#15887
Upstream-Fixes: mono/mono#15990
Upstream-Fixes: mono/mono#16032
Upstream-Fixes: mono/mono#16411
Upstream-Fixes: mono/mono#16486
Upstream-Fixes: https://github.com/mono/mono/issues/25709
Upstream-Fixes: https://github.com/mono/mono/issues/38821
Upstream-Fixes: xamarin#3112
Upstream-Fixes: xamarin#3168

Update `build-tools/automation/build.groovy` so that it fully cleans
the build tree before starting the build, so that the vestigial mono
submodule (removed in 0c9f83b) is *actually* removed from the build
tree, so that we don't inadvertently use *ancient* submodule contents.
jonpryor added a commit to xamarin/xamarin-android that referenced this issue Sep 7, 2019
Changes: http://github.com/mono/mono/compare/2c3aeaf3780de7392a0d3cbe4dcf86846eb4dffa...29b1ac19c961b959a09097dbc0fe4cd567cc5298

	$ git diff --shortstat 2c3aeaf3..29b1ac19
	 1528 files changed, 45421 insertions(+), 21967 deletions(-)

Changes: mono/api-doc-tools@d03e819...5da8127

	$ git diff --shortstat d03e8198..5da8127a
	 1001 files changed, 86168 insertions(+), 11863 deletions(-)

Changes: mono/api-snapshot@e09042d...1ca8e82

	$ git diff --shortstat e09042da..1ca8e82f
        28 files changed, 612 insertions(+), 217 deletions(-)

Changes: mono/cecil@a6c8f5e...cb6c1ca

	$ git diff --shortstat a6c8f5e1..cb6c1ca9
	 13 files changed, 233 insertions(+), 88 deletions(-)

Changes: mono/corefx@4806207...470e0e1

	$ git diff --shortstat 4806207f...470e0e10
	 4 files changed, 31 insertions(+), 12 deletions(-)

Changes: mono/linker@ebe2a1f...1f87de3

	$ git diff --shortstat ebe2a1f4...1f87de35
	 90 files changed, 3219 insertions(+), 1224 deletions(-)

Changes: xamarin/java.interop@75b1189...4fd3539

	$ git diff --shortstat 75b11891...4fd35393
	 34 files changed, 448 insertions(+), 52 deletions(-)

Fixes: #3112
Fixes: #3168

Context: https://bugs.winehq.org/show_bug.cgi?id=47561
Context: https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems/edit/967582
Context: dotnet/coreclr#25071
Context: dotnet/coreclr#25242
Context: dotnet/coreclr#25632
Context: dotnet/coreclr#25709
Context: dotnet/corefx#37955
Context: dotnet/corefx#38455
Context: mono/mono#7377
Context: mono/mono#8747
Context: mono/mono#9621
Context: mono/mono#9664
Context: mono/mono#9706
Context: mono/mono#10201
Context: mono/mono#10645
Context: mono/mono#10748
Context: mono/mono#10848
Context: mono/mono#12141
Context: mono/mono#13311
Context: mono/mono#13408
Context: mono/mono#13412
Context: mono/mono#13891
Context: mono/mono#13923
Context: mono/mono#13945
Context: mono/mono#14170
Context: mono/mono#14214
Context: mono/mono#14214
Context: mono/mono#14215
Context: mono/mono#14243
Context: mono/mono#14377
Context: mono/mono#14495
Context: mono/mono#14555
Context: mono/mono#14724
Context: mono/mono#14729
Context: mono/mono#14772
Context: mono/mono#14792
Context: mono/mono#14793
Context: mono/mono#14809
Context: mono/mono#14830
Context: mono/mono#14839
Context: mono/mono#14841
Context: mono/mono#14847
Context: mono/mono#14864
Context: mono/mono#14871
Context: mono/mono#14917
Context: mono/mono#14945
Context: mono/mono#14946
Context: mono/mono#14948
Context: mono/mono#14957
Context: mono/mono#14959
Context: mono/mono#14960
Context: mono/mono#14961
Context: mono/mono#14963
Context: mono/mono#14971
Context: mono/mono#14972
Context: mono/mono#14975
Context: mono/mono#15023
Context: mono/mono#15048
Context: mono/mono#15058
Context: mono/mono#15080
Context: mono/mono#15182
Context: mono/mono#15188
Context: mono/mono#15189
Context: mono/mono#15261
Context: mono/mono#15262
Context: mono/mono#15263
Context: mono/mono#15265
Context: mono/mono#15268
Context: mono/mono#15307
Context: mono/mono#15324
Context: mono/mono#15329
Context: mono/mono#15330
Context: mono/mono#15441
Context: mono/mono#15446
Context: mono/mono#15503
Context: mono/mono#15541
Context: mono/mono#15551
Context: mono/mono#15556
Context: mono/mono#15596
Context: mono/mono#15691
Context: mono/mono#15692
Context: mono/mono#15740
Context: mono/mono#15751
Context: mono/mono#15760
Context: mono/mono#15781
Context: mono/mono#15794
Context: mono/mono#15825
Context: mono/mono#15853
Context: mono/mono#15878
Context: mono/mono#15887
Context: mono/mono#15990
Context: mono/mono#16032
Context: mono/mono#16411
Context: mono/mono#16486
Context: https://github.com/mono/mono/issues/25709
Context: https://github.com/mono/mono/issues/38821

Update `build-tools/automation/build.groovy` so that it fully cleans
the build tree before starting the build, so that the vestigial mono
submodule (removed in 0c9f83b) is *actually* removed from the build
tree, so that we don't inadvertently use *ancient* submodule contents.
UnityAlex added a commit to Unity-Technologies/mono that referenced this issue Sep 12, 2019
…raint aren't blittlable. (mono#15761)

* [metadata] Fields whose types are gparams with a reference type constraint
aren't blittlable.
Don't try to layout the field to find out if it's blittable.
For gshared gparams, follow the blittability of the constraint.

Fixes certain recursive examples.

```
using System;

namespace TestRecursiveType
{
    class Program
    {
        static void Main(string[] args)
        {
            SubClass subC = new SubClass();
            Console.WriteLine(subC.GetTest());
        }
    }

    public struct ValueTest<U>
    {
        // When U is instantiated with T, from BaseClass, we know it'll be a
	// reference field, so we know the instantiation ValueTest<T> won't
	// be blittable.
        public readonly U value;
    }

    public abstract class BaseClass<T> where T : BaseClass<T>
    {
        public ValueTest<T> valueTest = default(ValueTest<T>);
    }

    public class SubClass : BaseClass<SubClass>
    {
        private String test = "test";

        public string GetTest()
        {
            return test;
        }
    }
}
```

Fixes mono#15760

---

The failure is happening when we are doing mono_class_setup_fields ("BaseClass<T>") which needs to decide for each field whether it is blittable or not. So therefore we are trying to decide if ValueTest<T> (that is: the ValueTest<U> field inside BaseClass<T>) is blittable or not.

So we instantiate U with T.
Now to decide whether VaueTest<T> is blittable or not, we look at every field.
So then we look at T value.
To decide if T is blittable we first check if it's a reference type.

That check is currently inadequate for generic parameters - what the PR adds is the ability to see if theres a T : class constraint or a T : C constraint - where C is some class. As soon as we know that T's constraint will force it to be a reference type we can definitely say that T won't be blittable without having to initialize C, at all.

Previously, Mono would see that T is some kind of type for which it couldn't definitively decide that it's a reference type and it would call: mono_class_setup_fields (field_class) which would then try to setup the fields of the parent class BaseClass<T>. And that would hit the recursion check.

Unity cherry-pick note: Needed to bring MONO_CLASS_IS_INTERFACE_INTERNAL
and mono_class_get_valuetype_class forward
UnityAlex added a commit to Unity-Technologies/mono that referenced this issue Sep 12, 2019
…raint aren't blittlable. (mono#15761)

* [metadata] Fields whose types are gparams with a reference type constraint
aren't blittlable.
Don't try to layout the field to find out if it's blittable.
For gshared gparams, follow the blittability of the constraint.

Fixes certain recursive examples.

```
using System;

namespace TestRecursiveType
{
    class Program
    {
        static void Main(string[] args)
        {
            SubClass subC = new SubClass();
            Console.WriteLine(subC.GetTest());
        }
    }

    public struct ValueTest<U>
    {
        // When U is instantiated with T, from BaseClass, we know it'll be a
	// reference field, so we know the instantiation ValueTest<T> won't
	// be blittable.
        public readonly U value;
    }

    public abstract class BaseClass<T> where T : BaseClass<T>
    {
        public ValueTest<T> valueTest = default(ValueTest<T>);
    }

    public class SubClass : BaseClass<SubClass>
    {
        private String test = "test";

        public string GetTest()
        {
            return test;
        }
    }
}
```

Fixes mono#15760

---

The failure is happening when we are doing mono_class_setup_fields ("BaseClass<T>") which needs to decide for each field whether it is blittable or not. So therefore we are trying to decide if ValueTest<T> (that is: the ValueTest<U> field inside BaseClass<T>) is blittable or not.

So we instantiate U with T.
Now to decide whether VaueTest<T> is blittable or not, we look at every field.
So then we look at T value.
To decide if T is blittable we first check if it's a reference type.

That check is currently inadequate for generic parameters - what the PR adds is the ability to see if theres a T : class constraint or a T : C constraint - where C is some class. As soon as we know that T's constraint will force it to be a reference type we can definitely say that T won't be blittable without having to initialize C, at all.

Previously, Mono would see that T is some kind of type for which it couldn't definitively decide that it's a reference type and it would call: mono_class_setup_fields (field_class) which would then try to setup the fields of the parent class BaseClass<T>. And that would hit the recursion check.

Unity cherry-pick note: Needed to bring MONO_CLASS_IS_INTERFACE_INTERNAL
and mono_class_get_valuetype_class forward
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
3 participants
You can’t perform that action at this time.