diff --git a/codegen/testserver/generated.go b/codegen/testserver/generated.go
index ea3c2f4854..34726a0087 100644
--- a/codegen/testserver/generated.go
+++ b/codegen/testserver/generated.go
@@ -9831,7 +9831,10 @@ func (ec *executionContext) _iIt_id(ctx context.Context, field graphql.Collected
 
 func (ec *executionContext) unmarshalInputInnerDirectives(ctx context.Context, obj interface{}) (InnerDirectives, error) {
 	var it InnerDirectives
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -9873,7 +9876,10 @@ func (ec *executionContext) unmarshalInputInnerDirectives(ctx context.Context, o
 
 func (ec *executionContext) unmarshalInputInnerInput(ctx context.Context, obj interface{}) (InnerInput, error) {
 	var it InnerInput
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -9893,7 +9899,10 @@ func (ec *executionContext) unmarshalInputInnerInput(ctx context.Context, obj in
 
 func (ec *executionContext) unmarshalInputInputDirectives(ctx context.Context, obj interface{}) (InputDirectives, error) {
 	var it InputDirectives
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -10013,7 +10022,10 @@ func (ec *executionContext) unmarshalInputInputDirectives(ctx context.Context, o
 
 func (ec *executionContext) unmarshalInputInputWithEnumValue(ctx context.Context, obj interface{}) (InputWithEnumValue, error) {
 	var it InputWithEnumValue
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -10033,7 +10045,10 @@ func (ec *executionContext) unmarshalInputInputWithEnumValue(ctx context.Context
 
 func (ec *executionContext) unmarshalInputNestedInput(ctx context.Context, obj interface{}) (NestedInput, error) {
 	var it NestedInput
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -10053,7 +10068,10 @@ func (ec *executionContext) unmarshalInputNestedInput(ctx context.Context, obj i
 
 func (ec *executionContext) unmarshalInputNestedMapInput(ctx context.Context, obj interface{}) (NestedMapInput, error) {
 	var it NestedMapInput
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -10073,7 +10091,10 @@ func (ec *executionContext) unmarshalInputNestedMapInput(ctx context.Context, ob
 
 func (ec *executionContext) unmarshalInputOuterInput(ctx context.Context, obj interface{}) (OuterInput, error) {
 	var it OuterInput
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -10093,7 +10114,10 @@ func (ec *executionContext) unmarshalInputOuterInput(ctx context.Context, obj in
 
 func (ec *executionContext) unmarshalInputRecursiveInputSlice(ctx context.Context, obj interface{}) (RecursiveInputSlice, error) {
 	var it RecursiveInputSlice
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -10113,7 +10137,10 @@ func (ec *executionContext) unmarshalInputRecursiveInputSlice(ctx context.Contex
 
 func (ec *executionContext) unmarshalInputSpecialInput(ctx context.Context, obj interface{}) (SpecialInput, error) {
 	var it SpecialInput
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
@@ -10133,7 +10160,10 @@ func (ec *executionContext) unmarshalInputSpecialInput(ctx context.Context, obj
 
 func (ec *executionContext) unmarshalInputValidInput(ctx context.Context, obj interface{}) (ValidInput, error) {
 	var it ValidInput
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
diff --git a/example/config/generated.go b/example/config/generated.go
index 4e985ada6b..a00b4fb177 100644
--- a/example/config/generated.go
+++ b/example/config/generated.go
@@ -1809,7 +1809,10 @@ func (ec *executionContext) ___Type_ofType(ctx context.Context, field graphql.Co
 
 func (ec *executionContext) unmarshalInputNewTodo(ctx context.Context, obj interface{}) (NewTodo, error) {
 	var it NewTodo
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
diff --git a/example/fileupload/generated.go b/example/fileupload/generated.go
index 9610785421..c53925c44b 100644
--- a/example/fileupload/generated.go
+++ b/example/fileupload/generated.go
@@ -1888,7 +1888,10 @@ func (ec *executionContext) ___Type_ofType(ctx context.Context, field graphql.Co
 
 func (ec *executionContext) unmarshalInputUploadFile(ctx context.Context, obj interface{}) (model.UploadFile, error) {
 	var it model.UploadFile
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
diff --git a/example/scalars/generated.go b/example/scalars/generated.go
index aa21a4bd1c..c819142b65 100644
--- a/example/scalars/generated.go
+++ b/example/scalars/generated.go
@@ -2146,7 +2146,10 @@ func (ec *executionContext) ___Type_ofType(ctx context.Context, field graphql.Co
 
 func (ec *executionContext) unmarshalInputSearchArgs(ctx context.Context, obj interface{}) (model.SearchArgs, error) {
 	var it model.SearchArgs
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
diff --git a/example/starwars/generated/exec.go b/example/starwars/generated/exec.go
index 3964d7f106..ed9e4a4760 100644
--- a/example/starwars/generated/exec.go
+++ b/example/starwars/generated/exec.go
@@ -3484,7 +3484,10 @@ func (ec *executionContext) ___Type_ofType(ctx context.Context, field graphql.Co
 
 func (ec *executionContext) unmarshalInputReviewInput(ctx context.Context, obj interface{}) (models.Review, error) {
 	var it models.Review
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
diff --git a/example/todo/generated.go b/example/todo/generated.go
index cb73c7c6c4..e1214fe3a6 100644
--- a/example/todo/generated.go
+++ b/example/todo/generated.go
@@ -1856,7 +1856,10 @@ func (ec *executionContext) ___Type_ofType(ctx context.Context, field graphql.Co
 
 func (ec *executionContext) unmarshalInputTodoInput(ctx context.Context, obj interface{}) (TodoInput, error) {
 	var it TodoInput
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
diff --git a/example/type-system-extension/generated.go b/example/type-system-extension/generated.go
index 2a8cc69338..ebc4b5727d 100644
--- a/example/type-system-extension/generated.go
+++ b/example/type-system-extension/generated.go
@@ -1874,7 +1874,10 @@ func (ec *executionContext) ___Type_ofType(ctx context.Context, field graphql.Co
 
 func (ec *executionContext) unmarshalInputTodoInput(ctx context.Context, obj interface{}) (TodoInput, error) {
 	var it TodoInput
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	for k, v := range asMap {
 		switch k {
diff --git a/integration/generated.go b/integration/generated.go
index 160d95ced5..0ff4474329 100644
--- a/integration/generated.go
+++ b/integration/generated.go
@@ -2013,7 +2013,10 @@ func (ec *executionContext) ___Type_ofType(ctx context.Context, field graphql.Co
 
 func (ec *executionContext) unmarshalInputDateFilter(ctx context.Context, obj interface{}) (models.DateFilter, error) {
 	var it models.DateFilter
-	var asMap = obj.(map[string]interface{})
+	asMap := map[string]interface{}{}
+	for k, v := range obj.(map[string]interface{}) {
+		asMap[k] = v
+	}
 
 	if _, present := asMap["timezone"]; !present {
 		asMap["timezone"] = "UTC"