diff --git a/src/Psalm/Internal/Analyzer/FunctionLike/ReturnTypeCollector.php b/src/Psalm/Internal/Analyzer/FunctionLike/ReturnTypeCollector.php
index a5f519f80..3a4d8da06 100644
--- a/src/Psalm/Internal/Analyzer/FunctionLike/ReturnTypeCollector.php
+++ b/src/Psalm/Internal/Analyzer/FunctionLike/ReturnTypeCollector.php
@@ -328,7 +328,7 @@ class ReturnTypeCollector
                 $generator_type = new Atomic\TGenericObject(
                     'Generator',
                     [
-                        $key_type ?: Type::getInt(),
+                        $key_type ? clone $key_type : Type::getInt(),
                         clone $value_type,
                         Type::getMixed(),
                         Type::getMixed()
diff --git a/src/Psalm/Internal/Analyzer/Statements/ExpressionAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/ExpressionAnalyzer.php
index 9630d2c5f..61f9ab6b0 100644
--- a/src/Psalm/Internal/Analyzer/Statements/ExpressionAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/ExpressionAnalyzer.php
@@ -1933,7 +1933,7 @@ class ExpressionAnalyzer
                     if ($expression_atomic_type instanceof Type\Atomic\TGenericObject) {
                         $yield_type = PropertyFetchAnalyzer::localizePropertyType(
                             $codebase,
-                            $yield_type,
+                            clone $yield_type,
                             $expression_atomic_type,
                             $classlike_storage,
                             $classlike_storage