scsi: lpfc: avoid false-positive gcc-8 warning

This is an interesting regression with gcc-8, showing a harmless warning
for correct code:

In file included from include/linux/kernel.h:13:0,
                 ...
                 from drivers/scsi/lpfc/lpfc_debugfs.c:23:
include/linux/printk.h:301:2: error: 'eq' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
  ^~~~~~
In file included from drivers/scsi/lpfc/lpfc_debugfs.c:58:0:
drivers/scsi/lpfc/lpfc_debugfs.h:451:31: note: 'eq' was declared here

I managed to reduce the warning into a small test case for gcc-8 that I
reported in the gcc bugzilla[1].

As a workaround, this changes the logic to move the two assignments of
'eq' out of the conditions and instead make the index conditional.  This
works for all configurations I tried and avoids adding a bogus
initialization.

Acked-by: James Smart <james.smart@broadcom.com>
Link: [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81958
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Arnd Bergmann 2017-08-25 01:10:00 +02:00 committed by Martin K. Petersen
parent 7362617319
commit 5fe5a6c9ac

View file

@ -478,16 +478,16 @@ lpfc_debug_dump_cq(struct lpfc_hba *phba, int qtype, int wqidx)
return;
for (eqidx = 0; eqidx < phba->io_channel_irqs; eqidx++) {
eq = phba->sli4_hba.hba_eq[eqidx];
if (cq->assoc_qid == eq->queue_id)
if (cq->assoc_qid == phba->sli4_hba.hba_eq[eqidx]->queue_id)
break;
}
if (eqidx == phba->io_channel_irqs) {
pr_err("Couldn't find EQ for CQ. Using EQ[0]\n");
eqidx = 0;
eq = phba->sli4_hba.hba_eq[0];
}
eq = phba->sli4_hba.hba_eq[eqidx];
if (qtype == DUMP_FCP || qtype == DUMP_NVME)
pr_err("%s CQ: WQ[Idx:%d|Qid%d]->CQ[Idx%d|Qid%d]"
"->EQ[Idx:%d|Qid:%d]:\n",