diff --git a/renderdoc/driver/vulkan/vk_outputwindow.cpp b/renderdoc/driver/vulkan/vk_outputwindow.cpp
index 2dd770c15..fe07c08fa 100644
--- a/renderdoc/driver/vulkan/vk_outputwindow.cpp
+++ b/renderdoc/driver/vulkan/vk_outputwindow.cpp
@@ -943,7 +943,7 @@ void VulkanReplay::BindOutputWindow(uint64_t id, bool depth)
   {
     // semaphore is short lived, so not wrapped, if it's cached (ideally)
     // then it should be wrapped
-    VkSemaphore sem;
+    VkSemaphore sem = VK_NULL_HANDLE;
     VkPipelineStageFlags stage = VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT;
     VkSemaphoreCreateInfo semInfo = {VK_STRUCTURE_TYPE_SEMAPHORE_CREATE_INFO, NULL, 0};