Fix for struct with undound members

expr.cpp

@@ -6784,9 +6784,12 @@ lUniformValueToVarying(FunctionEmitContext *ctx, llvm::Value *value,
             type->GetAsVaryingType()->LLVMType(g->ctx);
         llvm::Value *retValue = llvm::UndefValue::get(llvmType);
 
+        const StructType *structType = CastType<StructType>(type->GetAsVaryingType());
+
         for (int i = 0; i < collectionType->GetElementCount(); ++i) {
             llvm::Value *v = ctx->ExtractInst(value, i, "get_element");
-            if (collectionType->GetElementType(i)->IsVaryingType())
+            // If struct has "bound uniform" member, we don't need to cast it to varying
+            if (!(structType != NULL && structType->GetElementType(i)->IsUniformType()))
                 v = lUniformValueToVarying(ctx, v, collectionType->GetElementType(i));
             retValue = ctx->InsertInst(retValue, v, i, "set_element");
         }

tests/struct-test-128.ispc

@@ -0,0 +1,21 @@
+
+export uniform int width() { return programCount; }
+
+
+struct Foo {
+    float x;
+};
+
+export void f_fu(uniform float RET[], uniform float aFOO[], uniform float b) {
+    float a = aFOO[programIndex];
+    uniform Foo struct_1;
+    struct_1.x = b;
+    varying Foo struct_2 = struct_1;
+    RET[programIndex] = struct_2.x;
+}
+
+
+export void result(uniform float RET[]) {
+    RET[programIndex] = 5;
+}
+