[debugger] Fix assertion when trying to debug an async method in a valuetype (#21100)

* Fix * Assertion at C:\build\output\Unity-Technologies\mono\mono\mini\debugger-engine.c:1657, condition `is_ok (error)' not met, function:set_set_notification_for_wait_completion_flag, Could not execute the method because the containing type 'System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1[T_REF]', is not fully instantiated. assembly:<unknown assembly> type:<unknown type> member:(null)

* Adding test case.

* Remove unrelated changes.

* Fix test on interpreter.

3 files changed, 47 insertions, 1 deletions

diff --git a/mcs/class/Mono.Debugger.Soft/Makefile b/mcs/class/Mono.Debugger.Soft/Makefile
index 79938a8fb05..19b601e4689 100644
--- a/mcs/class/Mono.Debugger.Soft/Makefile
+++ b/mcs/class/Mono.Debugger.Soft/Makefile
@@ -29,7 +29,7 @@ test_output_dir=$(topdir)/class/lib/$(PROFILE)/tests
 $(test_output_dir):
 	mkdir -p $@
 
-build-dtest: $(test_output_dir)/dtest-app.exe $(test_output_dir)/dtest-excfilter.exe
+build-dtest: $(test_output_dir)/dtest-app.exe $(test_output_dir)/dtest-excfilter.exe $(test_output_dir)/dtest-app-opt.exe
 
 $(test_output_dir)/dtest-excfilter.exe: Test/dtest-excfilter.il | $(test_output_dir)
 	$(ILASM) -out:$@ /exe /debug Test/dtest-excfilter.il
@@ -37,6 +37,9 @@ $(test_output_dir)/dtest-excfilter.exe: Test/dtest-excfilter.il | $(test_output_
 $(test_output_dir)/dtest-app.exe: Test/dtest-app.cs $(TEST_HELPERS_SOURCES) | $(test_output_dir)
 	$(CSCOMPILE) -r:$(topdir)/class/lib/$(PROFILE)/mscorlib.dll -r:$(topdir)/class/lib/$(PROFILE)/System.Core.dll -r:$(topdir)/class/lib/$(PROFILE)/System.dll -r:$(topdir)/class/lib/$(PROFILE)/System.Runtime.CompilerServices.Unsafe.dll -sourcelink:Test/sourcelink.json -out:$@ -unsafe $(PLATFORM_DEBUG_FLAGS) $(DTEST_APP_FLAGS) -optimize- Test/dtest-app.cs $(TEST_HELPERS_SOURCES)
 
+$(test_output_dir)/dtest-app-opt.exe: Test/dtest-app-opt.cs $(TEST_HELPERS_SOURCES) | $(test_output_dir)
+	$(CSCOMPILE) -r:$(topdir)/class/lib/$(PROFILE)/mscorlib.dll -r:$(topdir)/class/lib/$(PROFILE)/System.Core.dll -r:$(topdir)/class/lib/$(PROFILE)/System.dll -sourcelink:Test/sourcelink.json -out:$@ -unsafe $(PLATFORM_DEBUG_FLAGS) $(DTEST_APP_FLAGS) -optimize+ Test/dtest-app-opt.cs $(TEST_HELPERS_SOURCES)
+
 TEST_HELPERS_SOURCES = \
 	../test-helpers/NetworkHelpers.cs \
 	Test/TypeLoadClass.cs
diff --git a/mcs/class/Mono.Debugger.Soft/Test/dtest-app-opt.cs b/mcs/class/Mono.Debugger.Soft/Test/dtest-app-opt.cs
new file mode 100644
index 00000000000..5dadc85ce04
--- /dev/null
+++ b/mcs/class/Mono.Debugger.Soft/Test/dtest-app-opt.cs
@@ -0,0 +1,23 @@
+using System;
+using System.Runtime.CompilerServices;
+using System.Diagnostics;
+using System.Threading;
+using System.Threading.Tasks;
+
+public class Tests
+{
+    public static int Main (String[] args) {
+        test_async_debug_generics ();
+		return 1;
+    }
+    [MethodImplAttribute (MethodImplOptions.NoInlining)]
+	public static void test_async_debug_generics () {
+		ExecuteAsync_Broken<object>().Wait ();
+	}
+
+	async static Task<T> ExecuteAsync_Broken<T>()
+	{
+		await Task.Delay(2);
+		return default;
+	}
+}
diff --git a/mcs/class/Mono.Debugger.Soft/Test/dtest.cs b/mcs/class/Mono.Debugger.Soft/Test/dtest.cs
index 2139072fe39..8402b668a1b 100644
--- a/mcs/class/Mono.Debugger.Soft/Test/dtest.cs
+++ b/mcs/class/Mono.Debugger.Soft/Test/dtest.cs
@@ -49,6 +49,7 @@ public class DebuggerTests
 	public static string agent_args = Environment.GetEnvironmentVariable ("DBG_AGENT_ARGS");
 
 	public static string dtest_app_path = "dtest-app.exe";
+	public static string dtest_app_opt_path = "dtest-app-opt.exe";
 	public static string dtest_excfilter_path = "dtest-excfilter.exe";
 
 	// Not currently used, but can be useful when debugging individual tests.
@@ -5211,6 +5212,25 @@ public class DebuggerTests
 		e = step_in_await ("MoveNext", e);
 	}
 
+
+	[Test]
+	public void TestAsyncDebugGenericsValueType () {
+		vm.Detach();
+		Start(dtest_app_opt_path);
+		MethodMirror async_method = entry_point.DeclaringType.GetMethod("test_async_debug_generics");
+		Assert.IsNotNull(async_method);
+		vm.SetBreakpoint(async_method, 0);
+		vm.Resume();
+		var e = GetNextEvent();
+		Assert.AreEqual(EventType.Breakpoint, e.EventType);
+		e = step_in_await("MoveNext", e);
+		e = step_in_await("MoveNext", e);
+		e = step_in_await("MoveNext", e);
+		vm.Exit(0);
+		vm = null;
+	}
+
+
 	[Test]
 	public void InvalidPointer_GetValue () {
 		vm.Detach ();