Fix a bug on default initialization of interface typed value. (#4249)

* Fix a bug on default initialization of interface typed value.

* Fix.

1 files changed, 4 insertions, 0 deletions

diff --git a/source/slang/slang-lower-to-ir.cpp b/source/slang/slang-lower-to-ir.cpp
index 8a8d235f5..80e73fe2b 100644
--- a/source/slang/slang-lower-to-ir.cpp
+++ b/source/slang/slang-lower-to-ir.cpp
@@ -4413,6 +4413,10 @@ struct ExprLoweringVisitorBase : public ExprVisitor<Derived, LoweredValInfo>
             {
                 return LoweredValInfo::simple(getBuilder()->getIntValue(irType, 0));
             }
+            else if (declRef.as<InterfaceDecl>())
+            {
+                return LoweredValInfo::simple(getBuilder()->emitDefaultConstruct(irType));
+            }
             else if (auto aggTypeDeclRef = declRef.as<AggTypeDecl>())
             {
                 List<IRInst*> args;