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scsi: qla2xxx: Simplify conditional check
authorNathan Chancellor <natechancellor@gmail.com>
Fri, 21 Sep 2018 00:27:23 +0000 (17:27 -0700)
committerMartin K. Petersen <martin.petersen@oracle.com>
Tue, 16 Oct 2018 22:25:23 +0000 (18:25 -0400)
Clang generates a warning when it sees a logical not followed by a
conditional operator like ==, >, or < because it thinks that the logical
not should be applied to the whole statement:

drivers/scsi/qla2xxx/qla_nx.c:3702:7: warning: logical not is only
applied to the left hand side of this comparison
[-Wlogical-not-parentheses]
                if (!qla2x00_eh_wait_for_pending_commands(vha, 0, 0,
                    ^
drivers/scsi/qla2xxx/qla_nx.c:3702:7: note: add parentheses after the
'!' to evaluate the comparison first
                if (!qla2x00_eh_wait_for_pending_commands(vha, 0, 0,
                    ^
                     (
drivers/scsi/qla2xxx/qla_nx.c:3702:7: note: add parentheses around left
hand side expression to silence this warning
                if (!qla2x00_eh_wait_for_pending_commands(vha, 0, 0,
                    ^
                    (
1 warning generated.

It assumes the author might have made a mistake in their logic:

if (!a == b) -> if (!(a == b))

Sometimes that is the case; other times, it's just a super convoluted
way of saying 'if (a)' when b = 0:

if (!1 == 0) -> if (0 == 0) -> if (true)

Alternatively:

if (!1 == 0) -> if (!!1) -> if (1)

Simplify this comparison so that Clang doesn't complain.

Link: https://github.com/ClangBuiltLinux/linux/issues/80
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/qla2xxx/qla_nx.c

index de2bc78..121e18b 100644 (file)
@@ -3699,8 +3699,8 @@ qla82xx_chip_reset_cleanup(scsi_qla_host_t *vha)
                spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
                /* Wait for pending cmds (physical and virtual) to complete */
-               if (!qla2x00_eh_wait_for_pending_commands(vha, 0, 0,
-                   WAIT_HOST) == QLA_SUCCESS) {
+               if (qla2x00_eh_wait_for_pending_commands(vha, 0, 0,
+                   WAIT_HOST)) {
                        ql_dbg(ql_dbg_init, vha, 0x00b3,
                            "Done wait for "
                            "pending commands.\n");