Allow mixing unspecialized and specialized existential parameters. (#1533)

* Allow mixing unspecialized and specialized existential parameters.

* Fixes.

1 files changed, 5 insertions, 0 deletions

diff --git a/source/slang/slang-ir-generics-lowering-context.cpp b/source/slang/slang-ir-generics-lowering-context.cpp
index b7e2917d5..9c4eb7856 100644
--- a/source/slang/slang-ir-generics-lowering-context.cpp
+++ b/source/slang/slang-ir-generics-lowering-context.cpp
@@ -197,6 +197,11 @@ namespace Slang
             SLANG_ASSERT(reqVal && reqVal->op == kIROp_AssociatedType);
             return lowerType(builder, reqVal, typeMapping);
         }
+        case kIROp_ExistentialBoxType:
+        {
+            auto existentialBoxType = static_cast<IRExistentialBoxType*>(paramType);
+            return lowerType(builder, existentialBoxType->getInterfaceType(), typeMapping);
+        }
         default:
         {
             bool translated = false;