Catch ambiguous interface method resolution exceptions (#15978)

Default interface methods might end up being ambiguous. This thows an exception we need to catch.

1 files changed, 22 insertions, 3 deletions

diff --git a/src/vm/jitinterface.cpp b/src/vm/jitinterface.cpp
index d08ba0cbe2..b238de8cba 100644
--- a/src/vm/jitinterface.cpp
+++ b/src/vm/jitinterface.cpp
@@ -8860,13 +8860,32 @@ CORINFO_METHOD_HANDLE CEEInfo::resolveVirtualMethodHelper(CORINFO_METHOD_HANDLE
                 pOwnerMT = pOwnerMT->GetCanonicalMethodTable();
             }
 
-            pDevirtMD = pDerivedMT->GetMethodDescForInterfaceMethod(TypeHandle(pOwnerMT), pBaseMD);
+            // In a try block because the interface method resolution might end up being
+            // ambiguous (diamond inheritance case of default interface methods).
+            EX_TRY
+            {
+                pDevirtMD = pDerivedMT->GetMethodDescForInterfaceMethod(TypeHandle(pOwnerMT), pBaseMD);
+            }
+            EX_CATCH
+            {
+            }
+            EX_END_CATCH(RethrowTransientExceptions)
         }
         else if (!pBaseMD->HasClassOrMethodInstantiation())
         {
-            pDevirtMD = pDerivedMT->GetMethodDescForInterfaceMethod(pBaseMD);
+            // In a try block because the interface method resolution might end up being
+            // ambiguous (diamond inheritance case of default interface methods).
+            EX_TRY
+            {
+                pDevirtMD = pDerivedMT->GetMethodDescForInterfaceMethod(pBaseMD);
+            }
+            EX_CATCH
+            {
+            }
+            EX_END_CATCH(RethrowTransientExceptions)
         }
-        else
+        
+        if (pDevirtMD == nullptr)
         {
             return nullptr;
         }