With -Wformat-nonliteral, gcc complains drivers/hwmon/hwmon.c: In function ‘hwmon_genattr’: drivers/hwmon/hwmon.c:282:6: warning: format not a string literal, argument types not checked [-Wformat-nonliteral] index + hwmon_attr_base(type)); Add a runtime check to ensure that the template indeed has a single %d printf specifier. Using fmtcheck() also makes gcc verify that the expression 'index + hwmon_attr_base(type)' is suitable for %d. Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> --- drivers/hwmon/hwmon.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/hwmon.c b/drivers/hwmon/hwmon.c index 33d51281272b..ec6f5f36b5fc 100644 --- a/drivers/hwmon/hwmon.c +++ b/drivers/hwmon/hwmon.c @@ -278,7 +278,8 @@ static struct attribute *hwmon_genattr(struct device *dev, if (type == hwmon_chip) { name = (char *)template; } else { - scnprintf(hattr->name, sizeof(hattr->name), template, + scnprintf(hattr->name, sizeof(hattr->name), + fmtcheck(template, "type%dwhat", 0), index + hwmon_attr_base(type)); name = hattr->name; } -- 2.19.1.6.gbde171bbf5