From 25d0fa42e256ccc69212c9a828718ab1e4e1dbfc Mon Sep 17 00:00:00 2001 From: Bastien Nocera Date: Wed, 12 Dec 2018 16:03:35 +0100 Subject: [PATCH] uru4000: Fix unused value in sm_read_regs() We don't need to assign urudev if we only want the size of one of its members. libfprint/drivers/uru4000.c:554:20: warning: Value stored to 'urudev' during its initialization is never read struct uru4k_dev *urudev = FP_INSTANCE_DATA(FP_DEV(dev)); ^~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ --- libfprint/drivers/uru4000.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/libfprint/drivers/uru4000.c b/libfprint/drivers/uru4000.c index 845a1862..94973858 100644 --- a/libfprint/drivers/uru4000.c +++ b/libfprint/drivers/uru4000.c @@ -545,16 +545,17 @@ static void sm_read_reg_cb(struct fp_img_dev *dev, int result, } } +#define member_size(type, member) sizeof(((type *)0)->member) + static void sm_read_regs(fpi_ssm *ssm, struct fp_img_dev *dev, uint16_t reg, uint16_t num_regs) { - struct uru4k_dev *urudev = FP_INSTANCE_DATA(FP_DEV(dev)); int r; - if (num_regs > sizeof(urudev->last_reg_rd)) { + if (num_regs > member_size(struct uru4k_dev, last_reg_rd)) { fpi_ssm_mark_failed(ssm, -EIO); return; }