diff --git a/vulkan/nulldrv/null_driver_gen.h b/vulkan/nulldrv/null_driver_gen.h
index 4052d26..43cd45e 100644
--- a/vulkan/nulldrv/null_driver_gen.h
+++ b/vulkan/nulldrv/null_driver_gen.h
@@ -138,7 +138,7 @@
 VKAPI_ATTR void CmdDrawIndexed(VkCommandBuffer commandBuffer, uint32_t indexCount, uint32_t instanceCount, uint32_t firstIndex, int32_t vertexOffset, uint32_t firstInstance);
 VKAPI_ATTR void CmdDrawIndirect(VkCommandBuffer commandBuffer, VkBuffer buffer, VkDeviceSize offset, uint32_t drawCount, uint32_t stride);
 VKAPI_ATTR void CmdDrawIndexedIndirect(VkCommandBuffer commandBuffer, VkBuffer buffer, VkDeviceSize offset, uint32_t drawCount, uint32_t stride);
-VKAPI_ATTR void CmdDispatch(VkCommandBuffer commandBuffer, uint32_t x, uint32_t y, uint32_t z);
+VKAPI_ATTR void CmdDispatch(VkCommandBuffer commandBuffer, uint32_t groupCountX, uint32_t groupCountY, uint32_t groupCountZ);
 VKAPI_ATTR void CmdDispatchIndirect(VkCommandBuffer commandBuffer, VkBuffer buffer, VkDeviceSize offset);
 VKAPI_ATTR void CmdCopyBuffer(VkCommandBuffer commandBuffer, VkBuffer srcBuffer, VkBuffer dstBuffer, uint32_t regionCount, const VkBufferCopy* pRegions);
 VKAPI_ATTR void CmdCopyImage(VkCommandBuffer commandBuffer, VkImage srcImage, VkImageLayout srcImageLayout, VkImage dstImage, VkImageLayout dstImageLayout, uint32_t regionCount, const VkImageCopy* pRegions);