* [usb:usb-testing 54/97] drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores]
@ 2021-08-18 22:09 kernel test robot
2021-08-19 7:47 ` Rui Miguel Silva
0 siblings, 1 reply; 4+ messages in thread
From: kernel test robot @ 2021-08-18 22:09 UTC (permalink / raw)
To: Rui Miguel Silva
Cc: clang-built-linux, kbuild-all, linux-usb, Greg Kroah-Hartman
[-- Attachment #1: Type: text/plain, Size: 22764 bytes --]
tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
head: e4788edc730a0d2b26e1ae1f08fbb3f635b92dbb
commit: 7de14c88272c05d86fce83a5cead36832ce3a424 [54/97] usb: isp1760: remove debug message as error
config: riscv-randconfig-c006-20210818 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project d2b574a4dea5b718e4386bf2e26af0126e5978ce)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install riscv cross compiling tool for clang build
# apt-get install binutils-riscv64-linux-gnu
# https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git/commit/?id=7de14c88272c05d86fce83a5cead36832ce3a424
git remote add usb https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
git fetch --no-tags usb usb-testing
git checkout 7de14c88272c05d86fce83a5cead36832ce3a424
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv clang-analyzer
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
clang-analyzer warnings: (new ones prefixed by >>)
^ ~
drivers/target/target_core_configfs.c:2627:23: warning: Value stored to 'alua_lu_gp_cg' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
struct config_group *alua_lu_gp_cg = &lu_gp->lu_gp_group;
^~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~
drivers/target/target_core_configfs.c:2627:23: note: Value stored to 'alua_lu_gp_cg' during its initialization is never read
struct config_group *alua_lu_gp_cg = &lu_gp->lu_gp_group;
^~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~
drivers/target/target_core_configfs.c:2731:2: warning: Value stored to 'alua_lu_gp_ci' is never read [clang-analyzer-deadcode.DeadStores]
alua_lu_gp_ci = &alua_lu_gp_cg->cg_item;
^ ~~~~~~~~~~~~~~~~~~~~~~~
drivers/target/target_core_configfs.c:2731:2: note: Value stored to 'alua_lu_gp_ci' is never read
alua_lu_gp_ci = &alua_lu_gp_cg->cg_item;
^ ~~~~~~~~~~~~~~~~~~~~~~~
drivers/target/target_core_configfs.c:2748:25: warning: Value stored to 'lu_gp' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
struct t10_alua_lu_gp *lu_gp = container_of(to_config_group(item),
^~~~~
drivers/target/target_core_configfs.c:2748:25: note: Value stored to 'lu_gp' during its initialization is never read
struct t10_alua_lu_gp *lu_gp = container_of(to_config_group(item),
^~~~~
drivers/target/target_core_configfs.c:3026:23: warning: Value stored to 'alua_tg_pt_gp_cg' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
struct config_group *alua_tg_pt_gp_cg = &tg_pt_gp->tg_pt_gp_group;
^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/target/target_core_configfs.c:3026:23: note: Value stored to 'alua_tg_pt_gp_cg' during its initialization is never read
struct config_group *alua_tg_pt_gp_cg = &tg_pt_gp->tg_pt_gp_group;
^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/target/target_core_configfs.c:3163:2: warning: Value stored to 'alua_tg_pt_gp_ci' is never read [clang-analyzer-deadcode.DeadStores]
alua_tg_pt_gp_ci = &alua_tg_pt_gp_cg->cg_item;
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/target/target_core_configfs.c:3163:2: note: Value stored to 'alua_tg_pt_gp_ci' is never read
alua_tg_pt_gp_ci = &alua_tg_pt_gp_cg->cg_item;
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/target/target_core_configfs.c:3179:28: warning: Value stored to 'tg_pt_gp' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(to_config_group(item),
^~~~~~~~
drivers/target/target_core_configfs.c:3179:28: note: Value stored to 'tg_pt_gp' during its initialization is never read
struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(to_config_group(item),
^~~~~~~~
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
6 warnings generated.
drivers/misc/eeprom/at24.c:334:2: warning: Value stored to 'client' is never read [clang-analyzer-deadcode.DeadStores]
client = at24_client->client;
^ ~~~~~~~~~~~~~~~~~~~
drivers/misc/eeprom/at24.c:334:2: note: Value stored to 'client' is never read
client = at24_client->client;
^ ~~~~~~~~~~~~~~~~~~~
drivers/misc/eeprom/at24.c:397:2: warning: Value stored to 'client' is never read [clang-analyzer-deadcode.DeadStores]
client = at24_client->client;
^ ~~~~~~~~~~~~~~~~~~~
drivers/misc/eeprom/at24.c:397:2: note: Value stored to 'client' is never read
client = at24_client->client;
^ ~~~~~~~~~~~~~~~~~~~
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
5 warnings generated.
drivers/usb/isp1760/isp1760-core.c:490:2: warning: Value stored to 'udc_enabled' is never read [clang-analyzer-deadcode.DeadStores]
udc_enabled = ((devflags & ISP1760_FLAG_ISP1763) ||
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-core.c:490:2: note: Value stored to 'udc_enabled' is never read
udc_enabled = ((devflags & ISP1760_FLAG_ISP1763) ||
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
4 warnings generated.
Suppressed 4 warnings (4 in non-user code).
Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
9 warnings generated.
>> drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores]
scratch = isp1760_hcd_read(hcd, HC_CHIP_ID_HIGH);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:735:2: note: Value stored to 'scratch' is never read
scratch = isp1760_hcd_read(hcd, HC_CHIP_ID_HIGH);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1855:38: warning: Division by zero [clang-analyzer-core.DivideZero]
&& !(urb->transfer_buffer_length %
^
drivers/usb/isp1760/isp1760-hcd.c:1887:2: note: Control jumps to 'case 3:' at line 1891
switch (usb_pipetype(urb->pipe)) {
^
drivers/usb/isp1760/isp1760-hcd.c:1893:3: note: Execution continues on line 1911
break;
^
drivers/usb/isp1760/isp1760-hcd.c:1911:6: note: Assuming the condition is false
if (usb_pipein(urb->pipe))
^
include/linux/usb.h:1937:27: note: expanded from macro 'usb_pipein'
#define usb_pipein(pipe) ((pipe) & USB_DIR_IN)
^~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1911:2: note: Taking false branch
if (usb_pipein(urb->pipe))
^
drivers/usb/isp1760/isp1760-hcd.c:1914:2: note: Calling 'packetize_urb'
packetize_urb(hcd, urb, &new_qtds, mem_flags);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1783:6: note: Assuming field 'transfer_buffer' is non-null
if (!urb->transfer_buffer && urb->transfer_buffer_length) {
^~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1783:28: note: Left side of '&&' is false
if (!urb->transfer_buffer && urb->transfer_buffer_length) {
^
drivers/usb/isp1760/isp1760-hcd.c:1792:2: note: Taking false branch
if (usb_pipein(urb->pipe))
^
drivers/usb/isp1760/isp1760-hcd.c:1797:2: note: Taking false branch
if (usb_pipecontrol(urb->pipe)) {
^
drivers/usb/isp1760/isp1760-hcd.c:1809:2: note: The value 0 is assigned to 'maxpacketsize'
maxpacketsize = max_packet(usb_maxpacket(urb->dev, urb->pipe,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1820:2: note: Loop condition is true. Entering loop body
for (;;) {
^
drivers/usb/isp1760/isp1760-hcd.c:1823:9: note: Calling 'qtd_alloc'
qtd = qtd_alloc(flags, urb, packet_type);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:980:6: note: Assuming 'qtd' is non-null, which participates in a condition later
if (!qtd)
^~~~
drivers/usb/isp1760/isp1760-hcd.c:980:2: note: Taking false branch
if (!qtd)
^
drivers/usb/isp1760/isp1760-hcd.c:989:2: note: Returning pointer (loaded from 'qtd'), which participates in a condition later
return qtd;
^~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1823:9: note: Returning from 'qtd_alloc'
qtd = qtd_alloc(flags, urb, packet_type);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1824:8: note: 'qtd' is non-null
if (!qtd)
^~~
drivers/usb/isp1760/isp1760-hcd.c:1824:3: note: Taking false branch
if (!qtd)
^
drivers/usb/isp1760/isp1760-hcd.c:1827:7: note: Assuming the condition is false
if (len > mem->blocks_size[ISP176x_BLOCK_NUM - 1])
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1827:3: note: Taking false branch
if (len > mem->blocks_size[ISP176x_BLOCK_NUM - 1])
^
drivers/usb/isp1760/isp1760-hcd.c:1836:7: note: 'len' is <= 0
if (len <= 0)
^~~
drivers/usb/isp1760/isp1760-hcd.c:1836:3: note: Taking true branch
if (len <= 0)
^
drivers/usb/isp1760/isp1760-hcd.c:1837:4: note: Execution continues on line 1844
break;
^
drivers/usb/isp1760/isp1760-hcd.c:1844:6: note: Assuming field 'transfer_buffer_length' is not equal to 0
if (urb->transfer_buffer_length != 0) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/usb/isp1760/isp1760-hcd.c:1844:2: note: Taking true branch
if (urb->transfer_buffer_length != 0) {
^
drivers/usb/isp1760/isp1760-hcd.c:1847:7: note: Assuming the condition is false
if (usb_pipecontrol(urb->pipe)) {
^
include/linux/usb.h:1946:32: note: expanded from macro 'usb_pipecontrol'
#define usb_pipecontrol(pipe) (usb_pipetype((pipe)) == PIPE_CONTROL)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/usb.h:1943:28: note: expanded from macro 'usb_pipetype'
#define usb_pipetype(pipe) (((pipe) >> 30) & 3)
^
drivers/usb/isp1760/isp1760-hcd.c:1847:3: note: Taking false branch
if (usb_pipecontrol(urb->pipe)) {
^
drivers/usb/isp1760/isp1760-hcd.c:1853:14: note: Assuming the condition is true
} else if (usb_pipebulk(urb->pipe)
vim +/scratch +735 drivers/usb/isp1760/isp1760-hcd.c
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 718
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 719 static int isp1760_hc_setup(struct usb_hcd *hcd)
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 720 {
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 721 struct isp1760_hcd *priv = hcd_to_priv(hcd);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 722 u32 atx_reset;
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 723 int result;
1da9e1c0687335 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 724 u32 scratch;
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 725 u32 pattern;
1da9e1c0687335 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 726
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 727 if (priv->is_isp1763)
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 728 pattern = 0xcafe;
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 729 else
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 730 pattern = 0xdeadcafe;
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 731
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 732 isp1760_hcd_write(hcd, HC_SCRATCH, pattern);
3faefc88c1a32b drivers/usb/host/isp1760-hcd.c Nate Case 2008-06-17 733
3faefc88c1a32b drivers/usb/host/isp1760-hcd.c Nate Case 2008-06-17 734 /* Change bus pattern */
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 @735 scratch = isp1760_hcd_read(hcd, HC_CHIP_ID_HIGH);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 736 scratch = isp1760_hcd_read(hcd, HC_SCRATCH);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 737 if (scratch != pattern) {
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 738 dev_err(hcd->self.controller, "Scratch test failed. 0x%08x\n", scratch);
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 739 return -ENODEV;
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 740 }
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 741
5171446a3aec60 drivers/usb/host/isp1760-hcd.c Laurent Pinchart 2015-01-21 742 /*
5171446a3aec60 drivers/usb/host/isp1760-hcd.c Laurent Pinchart 2015-01-21 743 * The RESET_HC bit in the SW_RESET register is supposed to reset the
5171446a3aec60 drivers/usb/host/isp1760-hcd.c Laurent Pinchart 2015-01-21 744 * host controller without touching the CPU interface registers, but at
5171446a3aec60 drivers/usb/host/isp1760-hcd.c Laurent Pinchart 2015-01-21 745 * least on the ISP1761 it seems to behave as the RESET_ALL bit and
5171446a3aec60 drivers/usb/host/isp1760-hcd.c Laurent Pinchart 2015-01-21 746 * reset the whole device. We thus can't use it here, so let's reset
5171446a3aec60 drivers/usb/host/isp1760-hcd.c Laurent Pinchart 2015-01-21 747 * the host controller through the EHCI USB Command register. The device
5171446a3aec60 drivers/usb/host/isp1760-hcd.c Laurent Pinchart 2015-01-21 748 * has been reset in core code anyway, so this shouldn't matter.
5171446a3aec60 drivers/usb/host/isp1760-hcd.c Laurent Pinchart 2015-01-21 749 */
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 750 isp1760_hcd_clear(hcd, ISO_BUF_FILL);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 751 isp1760_hcd_clear(hcd, INT_BUF_FILL);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 752 isp1760_hcd_clear(hcd, ATL_BUF_FILL);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 753
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 754 isp1760_hcd_set(hcd, HC_ATL_PTD_SKIPMAP);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 755 isp1760_hcd_set(hcd, HC_INT_PTD_SKIPMAP);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 756 isp1760_hcd_set(hcd, HC_ISO_PTD_SKIPMAP);
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 757
6bda21bc0941c1 drivers/usb/host/isp1760-hcd.c Arvid Brodin 2011-02-26 758 result = ehci_reset(hcd);
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 759 if (result)
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 760 return result;
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 761
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 762 /* Step 11 passed */
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 763
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 764 /* ATL reset */
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 765 if (priv->is_isp1763)
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 766 atx_reset = SW_RESET_RESET_ATX;
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 767 else
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 768 atx_reset = ALL_ATX_RESET;
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 769
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 770 isp1760_hcd_set(hcd, atx_reset);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 771 mdelay(10);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 772 isp1760_hcd_clear(hcd, atx_reset);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 773
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 774 if (priv->is_isp1763) {
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 775 isp1760_hcd_set(hcd, HW_OTG_DISABLE);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 776 isp1760_hcd_set(hcd, HW_SW_SEL_HC_DC_CLEAR);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 777 isp1760_hcd_set(hcd, HW_HC_2_DIS_CLEAR);
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 778 mdelay(10);
3faefc88c1a32b drivers/usb/host/isp1760-hcd.c Nate Case 2008-06-17 779
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 780 isp1760_hcd_set(hcd, HW_INTF_LOCK);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 781 }
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 782
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 783 isp1760_hcd_set(hcd, HC_INT_IRQ_ENABLE);
60d789f3bfbb74 drivers/usb/isp1760/isp1760-hcd.c Rui Miguel Silva 2021-05-13 784 isp1760_hcd_set(hcd, HC_ATL_IRQ_ENABLE);
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 785
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 786 return priv_init(hcd);
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 787 }
db11e47dd7b09b drivers/usb/host/isp1760-hcd.c Sebastian Siewior 2008-04-24 788
:::::: The code at line 735 was first introduced by commit
:::::: 60d789f3bfbb7428e6ba2949de70a6db8e12e8fa usb: isp1760: add support for isp1763
:::::: TO: Rui Miguel Silva <rui.silva@linaro.org>
:::::: CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
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^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [usb:usb-testing 54/97] drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores]
2021-08-18 22:09 [usb:usb-testing 54/97] drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores] kernel test robot
@ 2021-08-19 7:47 ` Rui Miguel Silva
2021-08-19 14:59 ` Greg Kroah-Hartman
0 siblings, 1 reply; 4+ messages in thread
From: Rui Miguel Silva @ 2021-08-19 7:47 UTC (permalink / raw)
To: kernel test robot
Cc: clang-built-linux, kbuild-all, linux-usb, Greg Kroah-Hartman
Hi,
On Wed Aug 18, 2021 at 11:09 PM WEST, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
> head: e4788edc730a0d2b26e1ae1f08fbb3f635b92dbb
> commit: 7de14c88272c05d86fce83a5cead36832ce3a424 [54/97] usb: isp1760: remove debug message as error
> config: riscv-randconfig-c006-20210818 (attached as .config)
> compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project d2b574a4dea5b718e4386bf2e26af0126e5978ce)
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # install riscv cross compiling tool for clang build
> # apt-get install binutils-riscv64-linux-gnu
> # https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git/commit/?id=7de14c88272c05d86fce83a5cead36832ce3a424
> git remote add usb https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
> git fetch --no-tags usb usb-testing
> git checkout 7de14c88272c05d86fce83a5cead36832ce3a424
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv clang-analyzer
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
>
> clang-analyzer warnings: (new ones prefixed by >>)
> ^ ~
> drivers/target/target_core_configfs.c:2627:23: warning: Value stored to 'alua_lu_gp_cg' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
> struct config_group *alua_lu_gp_cg = &lu_gp->lu_gp_group;
> ^~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~
> drivers/target/target_core_configfs.c:2627:23: note: Value stored to 'alua_lu_gp_cg' during its initialization is never read
> struct config_group *alua_lu_gp_cg = &lu_gp->lu_gp_group;
> ^~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~
> drivers/target/target_core_configfs.c:2731:2: warning: Value stored to 'alua_lu_gp_ci' is never read [clang-analyzer-deadcode.DeadStores]
> alua_lu_gp_ci = &alua_lu_gp_cg->cg_item;
> ^ ~~~~~~~~~~~~~~~~~~~~~~~
> drivers/target/target_core_configfs.c:2731:2: note: Value stored to 'alua_lu_gp_ci' is never read
> alua_lu_gp_ci = &alua_lu_gp_cg->cg_item;
> ^ ~~~~~~~~~~~~~~~~~~~~~~~
> drivers/target/target_core_configfs.c:2748:25: warning: Value stored to 'lu_gp' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
> struct t10_alua_lu_gp *lu_gp = container_of(to_config_group(item),
> ^~~~~
> drivers/target/target_core_configfs.c:2748:25: note: Value stored to 'lu_gp' during its initialization is never read
> struct t10_alua_lu_gp *lu_gp = container_of(to_config_group(item),
> ^~~~~
> drivers/target/target_core_configfs.c:3026:23: warning: Value stored to 'alua_tg_pt_gp_cg' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
> struct config_group *alua_tg_pt_gp_cg = &tg_pt_gp->tg_pt_gp_group;
> ^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/target/target_core_configfs.c:3026:23: note: Value stored to 'alua_tg_pt_gp_cg' during its initialization is never read
> struct config_group *alua_tg_pt_gp_cg = &tg_pt_gp->tg_pt_gp_group;
> ^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/target/target_core_configfs.c:3163:2: warning: Value stored to 'alua_tg_pt_gp_ci' is never read [clang-analyzer-deadcode.DeadStores]
> alua_tg_pt_gp_ci = &alua_tg_pt_gp_cg->cg_item;
> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/target/target_core_configfs.c:3163:2: note: Value stored to 'alua_tg_pt_gp_ci' is never read
> alua_tg_pt_gp_ci = &alua_tg_pt_gp_cg->cg_item;
> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/target/target_core_configfs.c:3179:28: warning: Value stored to 'tg_pt_gp' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
> struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(to_config_group(item),
> ^~~~~~~~
> drivers/target/target_core_configfs.c:3179:28: note: Value stored to 'tg_pt_gp' during its initialization is never read
> struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(to_config_group(item),
> ^~~~~~~~
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 6 warnings generated.
> drivers/misc/eeprom/at24.c:334:2: warning: Value stored to 'client' is never read [clang-analyzer-deadcode.DeadStores]
> client = at24_client->client;
> ^ ~~~~~~~~~~~~~~~~~~~
> drivers/misc/eeprom/at24.c:334:2: note: Value stored to 'client' is never read
> client = at24_client->client;
> ^ ~~~~~~~~~~~~~~~~~~~
> drivers/misc/eeprom/at24.c:397:2: warning: Value stored to 'client' is never read [clang-analyzer-deadcode.DeadStores]
> client = at24_client->client;
> ^ ~~~~~~~~~~~~~~~~~~~
> drivers/misc/eeprom/at24.c:397:2: note: Value stored to 'client' is never read
> client = at24_client->client;
> ^ ~~~~~~~~~~~~~~~~~~~
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 5 warnings generated.
> drivers/usb/isp1760/isp1760-core.c:490:2: warning: Value stored to 'udc_enabled' is never read [clang-analyzer-deadcode.DeadStores]
> udc_enabled = ((devflags & ISP1760_FLAG_ISP1763) ||
> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/usb/isp1760/isp1760-core.c:490:2: note: Value stored to 'udc_enabled' is never read
> udc_enabled = ((devflags & ISP1760_FLAG_ISP1763) ||
> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 4 warnings generated.
> Suppressed 4 warnings (4 in non-user code).
> Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> 9 warnings generated.
> >> drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores]
> scratch = isp1760_hcd_read(hcd, HC_CHIP_ID_HIGH);
> ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
yeah, this is desired behaviour, this read is only to make sure that
we make something different than the pattern to test go over the bus.
However I will take a look to this warning and other clang warnings
that I am seeing in this report.
------
Cheers,
Rui
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [usb:usb-testing 54/97] drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores]
2021-08-19 7:47 ` Rui Miguel Silva
@ 2021-08-19 14:59 ` Greg Kroah-Hartman
2021-08-19 15:06 ` Alan Stern
0 siblings, 1 reply; 4+ messages in thread
From: Greg Kroah-Hartman @ 2021-08-19 14:59 UTC (permalink / raw)
To: Rui Miguel Silva
Cc: kernel test robot, clang-built-linux, kbuild-all, linux-usb
On Thu, Aug 19, 2021 at 08:47:37AM +0100, Rui Miguel Silva wrote:
> Hi,
> On Wed Aug 18, 2021 at 11:09 PM WEST, kernel test robot wrote:
>
> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
> > head: e4788edc730a0d2b26e1ae1f08fbb3f635b92dbb
> > commit: 7de14c88272c05d86fce83a5cead36832ce3a424 [54/97] usb: isp1760: remove debug message as error
> > config: riscv-randconfig-c006-20210818 (attached as .config)
> > compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project d2b574a4dea5b718e4386bf2e26af0126e5978ce)
> > reproduce (this is a W=1 build):
> > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> > chmod +x ~/bin/make.cross
> > # install riscv cross compiling tool for clang build
> > # apt-get install binutils-riscv64-linux-gnu
> > # https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git/commit/?id=7de14c88272c05d86fce83a5cead36832ce3a424
> > git remote add usb https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
> > git fetch --no-tags usb usb-testing
> > git checkout 7de14c88272c05d86fce83a5cead36832ce3a424
> > # save the attached .config to linux build tree
> > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv clang-analyzer
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <lkp@intel.com>
> >
> >
> > clang-analyzer warnings: (new ones prefixed by >>)
> > ^ ~
> > drivers/target/target_core_configfs.c:2627:23: warning: Value stored to 'alua_lu_gp_cg' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
> > struct config_group *alua_lu_gp_cg = &lu_gp->lu_gp_group;
> > ^~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~
> > drivers/target/target_core_configfs.c:2627:23: note: Value stored to 'alua_lu_gp_cg' during its initialization is never read
> > struct config_group *alua_lu_gp_cg = &lu_gp->lu_gp_group;
> > ^~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~
> > drivers/target/target_core_configfs.c:2731:2: warning: Value stored to 'alua_lu_gp_ci' is never read [clang-analyzer-deadcode.DeadStores]
> > alua_lu_gp_ci = &alua_lu_gp_cg->cg_item;
> > ^ ~~~~~~~~~~~~~~~~~~~~~~~
> > drivers/target/target_core_configfs.c:2731:2: note: Value stored to 'alua_lu_gp_ci' is never read
> > alua_lu_gp_ci = &alua_lu_gp_cg->cg_item;
> > ^ ~~~~~~~~~~~~~~~~~~~~~~~
> > drivers/target/target_core_configfs.c:2748:25: warning: Value stored to 'lu_gp' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
> > struct t10_alua_lu_gp *lu_gp = container_of(to_config_group(item),
> > ^~~~~
> > drivers/target/target_core_configfs.c:2748:25: note: Value stored to 'lu_gp' during its initialization is never read
> > struct t10_alua_lu_gp *lu_gp = container_of(to_config_group(item),
> > ^~~~~
> > drivers/target/target_core_configfs.c:3026:23: warning: Value stored to 'alua_tg_pt_gp_cg' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
> > struct config_group *alua_tg_pt_gp_cg = &tg_pt_gp->tg_pt_gp_group;
> > ^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~
> > drivers/target/target_core_configfs.c:3026:23: note: Value stored to 'alua_tg_pt_gp_cg' during its initialization is never read
> > struct config_group *alua_tg_pt_gp_cg = &tg_pt_gp->tg_pt_gp_group;
> > ^~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~
> > drivers/target/target_core_configfs.c:3163:2: warning: Value stored to 'alua_tg_pt_gp_ci' is never read [clang-analyzer-deadcode.DeadStores]
> > alua_tg_pt_gp_ci = &alua_tg_pt_gp_cg->cg_item;
> > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
> > drivers/target/target_core_configfs.c:3163:2: note: Value stored to 'alua_tg_pt_gp_ci' is never read
> > alua_tg_pt_gp_ci = &alua_tg_pt_gp_cg->cg_item;
> > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~
> > drivers/target/target_core_configfs.c:3179:28: warning: Value stored to 'tg_pt_gp' during its initialization is never read [clang-analyzer-deadcode.DeadStores]
> > struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(to_config_group(item),
> > ^~~~~~~~
> > drivers/target/target_core_configfs.c:3179:28: note: Value stored to 'tg_pt_gp' during its initialization is never read
> > struct t10_alua_tg_pt_gp *tg_pt_gp = container_of(to_config_group(item),
> > ^~~~~~~~
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 6 warnings generated.
> > drivers/misc/eeprom/at24.c:334:2: warning: Value stored to 'client' is never read [clang-analyzer-deadcode.DeadStores]
> > client = at24_client->client;
> > ^ ~~~~~~~~~~~~~~~~~~~
> > drivers/misc/eeprom/at24.c:334:2: note: Value stored to 'client' is never read
> > client = at24_client->client;
> > ^ ~~~~~~~~~~~~~~~~~~~
> > drivers/misc/eeprom/at24.c:397:2: warning: Value stored to 'client' is never read [clang-analyzer-deadcode.DeadStores]
> > client = at24_client->client;
> > ^ ~~~~~~~~~~~~~~~~~~~
> > drivers/misc/eeprom/at24.c:397:2: note: Value stored to 'client' is never read
> > client = at24_client->client;
> > ^ ~~~~~~~~~~~~~~~~~~~
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 5 warnings generated.
> > drivers/usb/isp1760/isp1760-core.c:490:2: warning: Value stored to 'udc_enabled' is never read [clang-analyzer-deadcode.DeadStores]
> > udc_enabled = ((devflags & ISP1760_FLAG_ISP1763) ||
> > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > drivers/usb/isp1760/isp1760-core.c:490:2: note: Value stored to 'udc_enabled' is never read
> > udc_enabled = ((devflags & ISP1760_FLAG_ISP1763) ||
> > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 4 warnings generated.
> > Suppressed 4 warnings (4 in non-user code).
> > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > 9 warnings generated.
> > >> drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores]
> > scratch = isp1760_hcd_read(hcd, HC_CHIP_ID_HIGH);
> > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> yeah, this is desired behaviour, this read is only to make sure that
> we make something different than the pattern to test go over the bus.
> However I will take a look to this warning and other clang warnings
> that I am seeing in this report.
This is why I hate this type of warning, doing a read like this is
totally normal for drivers. Compilers that think this is something they
can ignore or warn about are just wrong.
greg k-h
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [usb:usb-testing 54/97] drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores]
2021-08-19 14:59 ` Greg Kroah-Hartman
@ 2021-08-19 15:06 ` Alan Stern
0 siblings, 0 replies; 4+ messages in thread
From: Alan Stern @ 2021-08-19 15:06 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: Rui Miguel Silva, kernel test robot, clang-built-linux,
kbuild-all, linux-usb
On Thu, Aug 19, 2021 at 04:59:04PM +0200, Greg Kroah-Hartman wrote:
> On Thu, Aug 19, 2021 at 08:47:37AM +0100, Rui Miguel Silva wrote:
> > Hi,
> > On Wed Aug 18, 2021 at 11:09 PM WEST, kernel test robot wrote:
> > > drivers/usb/isp1760/isp1760-core.c:490:2: warning: Value stored to 'udc_enabled' is never read [clang-analyzer-deadcode.DeadStores]
> > > udc_enabled = ((devflags & ISP1760_FLAG_ISP1763) ||
> > > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > drivers/usb/isp1760/isp1760-core.c:490:2: note: Value stored to 'udc_enabled' is never read
> > > udc_enabled = ((devflags & ISP1760_FLAG_ISP1763) ||
> > > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > > Suppressed 4 warnings (4 in non-user code).
> > > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > > 4 warnings generated.
> > > Suppressed 4 warnings (4 in non-user code).
> > > Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well.
> > > 9 warnings generated.
> > > >> drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores]
> > > scratch = isp1760_hcd_read(hcd, HC_CHIP_ID_HIGH);
> > > ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > yeah, this is desired behaviour, this read is only to make sure that
> > we make something different than the pattern to test go over the bus.
> > However I will take a look to this warning and other clang warnings
> > that I am seeing in this report.
>
> This is why I hate this type of warning, doing a read like this is
> totally normal for drivers. Compilers that think this is something they
> can ignore or warn about are just wrong.
No, no. The compiler isn't complaining about the call to
isp1760_hcd_read(); it's complaining about the fact that scratch
stores the return value. Since the value isn't used anywhere, there's
no point in storing it.
You can get rid of the warning by changing the line to:
(void) isp1760_hcd_read(hcd, HC_CHIP_ID_HIGH);
(The (void) cast isn't really necessary; it's just there to point out
that the return value is being thrown away. You can omit it if you
prefer.)
Likewise for the store to udc_enabled.
Alan Stern
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-08-19 15:06 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-18 22:09 [usb:usb-testing 54/97] drivers/usb/isp1760/isp1760-hcd.c:735:2: warning: Value stored to 'scratch' is never read [clang-analyzer-deadcode.DeadStores] kernel test robot
2021-08-19 7:47 ` Rui Miguel Silva
2021-08-19 14:59 ` Greg Kroah-Hartman
2021-08-19 15:06 ` Alan Stern
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