x86_64 allmodconfig build with W=1 gives these warnings: drivers/ata/pata_cs5535.c: In function ‘cs5535_set_piomode’: drivers/ata/pata_cs5535.c:93:11: error: variable ‘dummy’ set but not used [-Werror=unused-but-set-variable] u32 reg, dummy; ^~~~~ drivers/ata/pata_cs5535.c: In function ‘cs5535_set_dmamode’: drivers/ata/pata_cs5535.c:132:11: error: variable ‘dummy’ set but not used [-Werror=unused-but-set-variable] u32 reg, dummy; ^~~~~ cc1: all warnings being treated as errors Mark variables 'dummy' as "maybe unused" as they are only ever written in rdmsr() calls. Signed-off-by: John Garry <john.garry@xxxxxxxxxx> Reviewed-by: Sergey Shtylyov <s.shtylyov@xxxxxx> --- Differences to v1: - Add RB tag (thanks!) - Fix commit message diff --git a/drivers/ata/pata_cs5535.c b/drivers/ata/pata_cs5535.c index 6725931f3c35..c2c3238ff84b 100644 --- a/drivers/ata/pata_cs5535.c +++ b/drivers/ata/pata_cs5535.c @@ -90,7 +90,7 @@ static void cs5535_set_piomode(struct ata_port *ap, struct ata_device *adev) static const u16 pio_cmd_timings[5] = { 0xF7F4, 0x53F3, 0x13F1, 0x5131, 0x1131 }; - u32 reg, dummy; + u32 reg, __maybe_unused dummy; struct ata_device *pair = ata_dev_pair(adev); int mode = adev->pio_mode - XFER_PIO_0; @@ -129,7 +129,7 @@ static void cs5535_set_dmamode(struct ata_port *ap, struct ata_device *adev) static const u32 mwdma_timings[3] = { 0x7F0FFFF3, 0x7F035352, 0x7F024241 }; - u32 reg, dummy; + u32 reg, __maybe_unused dummy; int mode = adev->dma_mode; rdmsr(ATAC_CH0D0_DMA + 2 * adev->devno, reg, dummy); -- 2.35.3