On 28/06/2022 09:59, Damien Le Moal wrote:
On 6/27/22 22:12, John Garry wrote:
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" to satisfy when rdmsr() is
stubbed, which is the same as what we already do in pata_cs5536.c .
Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
Looks good, but I wonder why I am not getting this warning. I always do
W=1 and C=1 builds. I tried allmodconfig now and I am not getting the
warning...
eh, I'm not sure why. It's the only driver in drivers/ata/ which gives
such a problem.
I'm using gcc 9:
gcc version 9.3.1 20200406 [revision
6db837a5288ee3ca5ec504fbd5a765817e556ac2] (SUSE Linux)
Then I cross-compiled from my arm64 machine (to x86) and still got it:
john@ubuntu:~/kernel-dev$ /usr/bin/x86_64-linux-gnu-gcc --version
x86_64-linux-gnu-gcc (Ubuntu 7.5.0-3ubuntu1~18.04) 7.5.0
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);
