diff --git a/src/linker/Linker/TypeReferenceExtensions.cs b/src/linker/Linker/TypeReferenceExtensions.cs
index 9dbcd52589c2..cddf27c89b77 100644
--- a/src/linker/Linker/TypeReferenceExtensions.cs
+++ b/src/linker/Linker/TypeReferenceExtensions.cs
@@ -45,7 +45,8 @@ public static StringBuilder GetDisplayNameWithoutNamespace (this TypeReference t
 							else
 								PrependGenericParameters (type.GenericParameters.Skip (declaringTypeGenericParametersCount).ToList (), sb);
 
-							simpleName = type.Name.Substring (0, type.Name.IndexOf ('`'));
+							int explicitArityIndex = type.Name.IndexOf ('`');
+							simpleName = explicitArityIndex != -1 ? type.Name.Substring (0, explicitArityIndex) : type.Name;
 						} else
 							simpleName = type.Name;