Provoke the issue

Mono.Cecil.sln

@@ -19,6 +19,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Mono.Cecil.Rocks", "rocks\M
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Mono.Cecil.Rocks.Tests", "rocks\Test\Mono.Cecil.Rocks.Tests.csproj", "{EF768F7A-3C08-45EE-8A7E-BB5A81BADB7B}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Cecil.11.3.issue", "repro\Cecil.11.3.issue.csproj", "{BC2C29E7-BE9E-4087-9F7E-D9BCAFCA635E}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -57,6 +59,10 @@ Global
 		{EF768F7A-3C08-45EE-8A7E-BB5A81BADB7B}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{EF768F7A-3C08-45EE-8A7E-BB5A81BADB7B}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{EF768F7A-3C08-45EE-8A7E-BB5A81BADB7B}.Release|Any CPU.Build.0 = Release|Any CPU
+		{BC2C29E7-BE9E-4087-9F7E-D9BCAFCA635E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{BC2C29E7-BE9E-4087-9F7E-D9BCAFCA635E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{BC2C29E7-BE9E-4087-9F7E-D9BCAFCA635E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{BC2C29E7-BE9E-4087-9F7E-D9BCAFCA635E}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

repro/Cecil.11.3.issue.csproj

@@ -0,0 +1,31 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp2.0</TargetFramework>
+    <RootNamespace>Issue</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Compile Include="Program.cs" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <None Include="Sample3.dll" />
+    <None Include="Sample3.dll.mdb" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\Mono.Cecil.csproj" />
+    <ProjectReference Include="..\symbols\mdb\Mono.Cecil.Mdb.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <None Update="Sample3.dll">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+    <None Update="Sample3.dll.mdb">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+  </ItemGroup>
+</Project>

repro/Program.cs

@@ -0,0 +1,36 @@
+using System.IO;
+using System.Linq;
+using System.Reflection;
+using Mono.Cecil;
+using Mono.Cecil.Cil;
+using Mono.Cecil.Mdb;
+
+public class Issue
+{
+  private static void Main(string[] args)
+  {
+    var here = Assembly.GetExecutingAssembly().Location;
+    var target = Path.Combine(
+      Path.GetDirectoryName(here),
+      "Sample3.dll"
+      );
+
+    var definition = AssemblyDefinition.ReadAssembly(target);
+
+    var provider = new MdbReaderProvider();
+    var reader = provider.GetSymbolReader(definition.MainModule, target);
+    definition.MainModule.ReadSymbols(reader);
+
+    var pathGetterDef =
+               definition.MainModule.GetTypes().
+                 SelectMany(t => t.Methods).
+                 First(m => m.Name.Equals("get_Defer"));
+
+    var body = pathGetterDef.Body;
+    var worker = body.GetILProcessor();
+    var initialBody = body.Instructions.ToList();
+    var head = initialBody.First();
+    var opcode = worker.Create(OpCodes.Ldc_I4_1);
+    worker.InsertBefore(head, opcode);
+  }
+}