git: 6ef6d3424f15 - stable/12 - Fix unused variable warning in ffs_snapshot.c

The branch stable/12 has been updated by dim:

URL: https://cgit.FreeBSD.org/src/commit/?id=6ef6d3424f158a797d280ebd3103d4d833d41230

commit 6ef6d3424f158a797d280ebd3103d4d833d41230
Author:     Dimitry Andric <dim@FreeBSD.org>
AuthorDate: 2022-07-26 19:30:41 +0000
Commit:     Dimitry Andric <dim@FreeBSD.org>
CommitDate: 2022-07-29 18:43:14 +0000

    Fix unused variable warning in ffs_snapshot.c
    
    With clang 15, the following -Werror warning is produced:
    
        sys/ufs/ffs/ffs_snapshot.c:204:7: error: variable 'redo' set but not used [-Werror,-Wunused-but-set-variable]
                long redo = 0, snaplistsize = 0;
                     ^
    
    The 'redo' variable is only used when DIAGNOSTIC is defined. Ensure it
    is only declared and set in that case.
    
    MFC after:      3 days
    
    (cherry picked from commit c9dde6f0c713a027266c52cf94a33a086348c566)
---
 sys/ufs/ffs/ffs_snapshot.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/sys/ufs/ffs/ffs_snapshot.c b/sys/ufs/ffs/ffs_snapshot.c
index a65616fd04e0..1700a4094ae7 100644
--- a/sys/ufs/ffs/ffs_snapshot.c
+++ b/sys/ufs/ffs/ffs_snapshot.c
@@ -214,7 +214,10 @@ ffs_snapshot(mp, snapfile)
 	uint64_t flag;
 	struct timespec starttime = {0, 0}, endtime;
 	char saved_nice = 0;
-	long redo = 0, snaplistsize = 0;
+#ifdef DIAGNOSTIC
+	long redo = 0;
+#endif
+	long snaplistsize = 0;
 	int32_t *lp;
 	void *space;
 	struct fs *copy_fs = NULL, *fs;
@@ -457,7 +460,9 @@ restart:
 	for (cg = 0; cg < fs->fs_ncg; cg++) {
 		if ((ACTIVECGNUM(fs, cg) & ACTIVECGOFF(cg)) != 0)
 			continue;
+#ifdef DIAGNOSTIC
 		redo++;
+#endif
 		error = UFS_BALLOC(vp, lfragtosize(fs, cgtod(fs, cg)),
 		    fs->fs_bsize, KERNCRED, 0, &nbp);
 		if (error)