Fix #121066: Mark INITCLASS helpers as mutating heap to respect static constructor side-effects

src/coreclr/jit/utils.cpp

@@ -1727,7 +1727,7 @@ void HelperCallProperties::init()
 
             case CORINFO_HELP_INITCLASS:
             case CORINFO_HELP_INITINSTCLASS:
-                isPure      = true;
+                mutatesHeap = true;
                 mayRunCctor = true;
                 break;
 

src/tests/JIT/Regression/JitBlue/Runtime_121066/Runtime_121066.cs

@@ -0,0 +1,100 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Runtime.CompilerServices;
+using Xunit;
+
+public class Runtime_121066
+{
+    public static int preciseInitCctorsRun = 0;
+
+    class MyPreciseInitClass<T>
+    {
+        static MyPreciseInitClass()
+        {
+            preciseInitCctorsRun++;
+        }
+
+        public static void TriggerCctorClass()
+        {
+        }
+
+        public static void TriggerCctorMethod<U>()
+        { }
+    }
+
+    class MyClass<T>
+    {
+        static Type staticVarType = typeof(MyClass<T>);
+        public Type GetTypeOf()
+        {
+            return typeof(MyClass<T>);
+        }
+        public static Type GetTypeOfStatic()
+        {
+            return typeof(MyClass<T>);
+        }
+
+        public static Type GetTypeThroughStaticVar()
+        {
+            return staticVarType;
+        }
+    }
+
+    [Fact]
+    public static void TestEntryPoint()
+    {
+        Assert.True(TestPreciseInitCctors());
+    }
+
+    public static bool TestPreciseInitCctors()
+    {
+        if (preciseInitCctorsRun != 0)
+        {
+            Console.WriteLine("preciseInitCctorsRun should be 0, but is {0}", preciseInitCctorsRun);
+            return false;
+        }
+        MyPreciseInitClass<int>.TriggerCctorClass();
+        if (preciseInitCctorsRun != 1)
+        {
+            Console.WriteLine("preciseInitCctorsRun should be 1, but is {0}", preciseInitCctorsRun);
+            return false;
+        }
+        MyPreciseInitClass<short>.TriggerCctorMethod<int>();
+        if (preciseInitCctorsRun != 2)
+        {
+            Console.WriteLine("TriggerCctorClass should return 2, but is {0}", preciseInitCctorsRun);
+            return false;
+        }
+
+        object o = new MyPreciseInitClass<double>();
+        if (preciseInitCctorsRun != 3)
+        {
+            Console.WriteLine("TriggerCctorClass should return 3, but is {0}", preciseInitCctorsRun);
+            return false;
+        }
+
+        MyPreciseInitClass<object>.TriggerCctorClass();
+        if (preciseInitCctorsRun != 4)
+        {
+            Console.WriteLine("preciseInitCctorsRun should be 4 but is {0}", preciseInitCctorsRun);
+            return false;
+        }
+        MyPreciseInitClass<string>.TriggerCctorMethod<object>();
+        if (preciseInitCctorsRun != 5)
+        {
+            Console.WriteLine("TriggerCctorClass should return 5, but is {0}", preciseInitCctorsRun);
+            return false;
+        }
+
+        o = new MyPreciseInitClass<Type>();
+        if (preciseInitCctorsRun != 6)
+        {
+            Console.WriteLine("TriggerCctorClass should return 6,  but is {0}", preciseInitCctorsRun);
+            return false;
+        }
+
+        return true;
+    }
+}

src/tests/JIT/Regression/JitBlue/Runtime_121066/Runtime_121066.csproj

@@ -0,0 +1,12 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <DebugType>None</DebugType>
+    <Optimize>True</Optimize>
+    <!-- Needed for CLRTestEnvironmentVariable -->
+    <RequiresProcessIsolation>true</RequiresProcessIsolation>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="$(MSBuildProjectName).cs" />
+    <CLRTestEnvironmentVariable Include="DOTNET_TieredCompilation" Value="0" />
+  </ItemGroup>
+</Project>