From d0e34f015460b0ef2c359b3489b29c10cae5ed6e Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Fri, 30 May 2014 11:35:54 -0600 Subject: [PATCH] drivers/vfio: Rework offsetofend() commit b13460b92093b29347e99d6c3242e350052b62cd upstream. The macro offsetofend() introduces unnecessary temporary variable "tmp". The patch avoids that and saves a bit memory in stack. Signed-off-by: Gavin Shan Signed-off-by: Alex Williamson Signed-off-by: Jiri Slaby --- include/linux/vfio.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/include/linux/vfio.h b/include/linux/vfio.h index 24579a0312a0c..43f6bf4f85850 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -86,9 +86,8 @@ extern void vfio_unregister_iommu_driver( * from user space. This allows us to easily determine if the provided * structure is sized to include various fields. */ -#define offsetofend(TYPE, MEMBER) ({ \ - TYPE tmp; \ - offsetof(TYPE, MEMBER) + sizeof(tmp.MEMBER); }) \ +#define offsetofend(TYPE, MEMBER) \ + (offsetof(TYPE, MEMBER) + sizeof(((TYPE *)0)->MEMBER)) /* * External user API -- 2.47.2