storage: shut up gcc and remove unused variables.

src/lxc/storage/loop.c

@@ -137,7 +137,7 @@ int loop_clonepaths(struct lxc_storage *orig, struct lxc_storage *new,
 int loop_create(struct lxc_storage *bdev, const char *dest, const char *n,
 		struct bdev_specs *specs)
 {
-	__do_free char *srcdev;
+	__do_free char *srcdev = NULL;
 	const char *fstype;
 	uint64_t sz;
 	int ret, len;

src/lxc/storage/lvm.c

@@ -114,7 +114,7 @@ static int do_lvm_create(const char *path, uint64_t size, const char *thinpool)
 	char *pathdup, *vg, *lv;
 	char cmd_output[PATH_MAX];
 	char sz[24];
-	__do_free char *tp;
+	__do_free char *tp = NULL;
 	struct lvcreate_args cmd_args = {0};
 
 	ret = snprintf(sz, 24, "%" PRIu64 "b", size);
@@ -268,7 +268,7 @@ int lvm_umount(struct lxc_storage *bdev)
 #define __LVSCMD "lvs --unbuffered --noheadings -o lv_attr %s 2>/dev/null"
 int lvm_compare_lv_attr(const char *path, int pos, const char expected)
 {
-	__do_free char *cmd;
+	__do_free char *cmd = NULL;
 	struct lxc_popen_FILE *f;
 	int ret, status;
 	size_t len;

src/lxc/storage/nbd.c

@@ -62,7 +62,7 @@ static bool wait_for_partition(const char *path);
 
 bool attach_nbd(char *src, struct lxc_conf *conf)
 {
-	__do_free char *orig;
+	__do_free char *orig = NULL;
 	char *p, path[50];
 	int i = 0;
 

src/lxc/storage/storage.c

@@ -568,9 +568,8 @@ struct lxc_storage *storage_create(const char *dest, const char *type,
 
 	/* -B lvm,dir */
 	if (strchr(type, ',')) {
-		__do_free char *dup;
+		__do_free char *dup = NULL;
 		char *token;
-		size_t len;
 
 		dup = must_copy_string(type);
 		lxc_iterate_parts(token, dup, ",") {