libblkid: [superblocks] fix compiler warnings [-Wunused-parameter -Wsign-compare]

Signed-off-by: Karel Zak <kzak@redhat.com>

22 files changed, 83 insertions, 57 deletions

diff --git a/libblkid/src/superblocks/adaptec_raid.c b/libblkid/src/superblocks/adaptec_raid.c
index 570e75e9f..02e900df0 100644
--- a/libblkid/src/superblocks/adaptec_raid.c
+++ b/libblkid/src/superblocks/adaptec_raid.c
@@ -73,7 +73,8 @@ struct adaptec_metadata {
 #define AD_SIGNATURE	0x4450544D	/* "DPTM" */
 #define AD_MAGIC	0x37FC4D1E
 
-static int probe_adraid(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_adraid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	uint64_t off;
 	struct adaptec_metadata *ad;
diff --git a/libblkid/src/superblocks/befs.c b/libblkid/src/superblocks/befs.c
index c78dc208e..62414ec61 100644
--- a/libblkid/src/superblocks/befs.c
+++ b/libblkid/src/superblocks/befs.c
@@ -158,9 +158,9 @@ unsigned char *get_tree_node(blkid_probe pr, const struct befs_super_block *bs,
 				const struct data_stream *ds,
 				int64_t start, uint32_t length, int fs_le)
 {
-	if (start < FS64_TO_CPU(ds->max_direct_range, fs_le)) {
+	if (start < (int64_t) FS64_TO_CPU(ds->max_direct_range, fs_le)) {
 		int64_t br_len;
-		int i;
+		size_t i;
 
 		for (i = 0; i < NUM_DIRECT_BLOCKS; i++) {
 			br_len = (int64_t) FS16_TO_CPU(ds->direct[i].len, fs_le)
@@ -172,7 +172,7 @@ unsigned char *get_tree_node(blkid_probe pr, const struct befs_super_block *bs,
 			else
 				start -= br_len;
 		}
-	} else if (start < FS64_TO_CPU(ds->max_indirect_range, fs_le)) {
+	} else if (start < (int64_t) FS64_TO_CPU(ds->max_indirect_range, fs_le)) {
 		struct block_run *br;
 		int64_t max_br, br_len, i;
 
@@ -195,11 +195,11 @@ unsigned char *get_tree_node(blkid_probe pr, const struct befs_super_block *bs,
 			else
 				start -= br_len;
 		}
-	} else if (start < FS64_TO_CPU(ds->max_double_indirect_range, fs_le)) {
+	} else if (start < (int64_t) FS64_TO_CPU(ds->max_double_indirect_range, fs_le)) {
 		struct block_run *br;
 		int64_t di_br_size, br_per_di_br, di_index, i_index;
 
-		start -= FS64_TO_CPU(ds->max_indirect_range, fs_le);
+		start -= (int64_t) FS64_TO_CPU(ds->max_indirect_range, fs_le);
 		di_br_size = (int64_t) FS16_TO_CPU(ds->double_indirect.len,
 				fs_le) << FS32_TO_CPU(bs->block_shift, fs_le);
 		br_per_di_br = di_br_size / sizeof(struct block_run);
@@ -259,7 +259,7 @@ int64_t get_key_value(blkid_probe pr, const struct befs_super_block *bs,
 	if (!bh)
 		return -1;
 
-	if (FS32_TO_CPU(bh->magic, fs_le) != BPLUSTREE_MAGIC)
+	if ((int32_t) FS32_TO_CPU(bh->magic, fs_le) != BPLUSTREE_MAGIC)
 		return -1;
 
 	node_pointer = FS64_TO_CPU(bh->root_node_pointer, fs_le);
@@ -285,7 +285,7 @@ int64_t get_key_value(blkid_probe pr, const struct befs_super_block *bs,
 		cmp = compare_keys(bn->name, keylengths, last, key, strlen(key),
 									fs_le);
 		if (cmp == 0) {
-			if (FS64_TO_CPU(bn->overflow_link, fs_le)
+			if ((int64_t) FS64_TO_CPU(bn->overflow_link, fs_le)
 							== BPLUSTREE_NULL)
 				return FS64_TO_CPU(values[last], fs_le);
 			else
@@ -299,7 +299,7 @@ int64_t get_key_value(blkid_probe pr, const struct befs_super_block *bs,
 				cmp = compare_keys(bn->name, keylengths, mid,
 						key, strlen(key), fs_le);
 				if (cmp == 0) {
-					if (FS64_TO_CPU(bn->overflow_link,
+					if ((int64_t) FS64_TO_CPU(bn->overflow_link,
 						fs_le) == BPLUSTREE_NULL)
 						return FS64_TO_CPU(values[mid],
 									fs_le);
@@ -316,7 +316,8 @@ int64_t get_key_value(blkid_probe pr, const struct befs_super_block *bs,
 			else
 				node_pointer = FS64_TO_CPU(values[mid], fs_le);
 		}
-	} while (FS64_TO_CPU(bn->overflow_link, fs_le) != BPLUSTREE_NULL);
+	} while ((int64_t) FS64_TO_CPU(bn->overflow_link, fs_le)
+						!= BPLUSTREE_NULL);
 	return 0;
 }
 
@@ -355,8 +356,8 @@ int get_uuid(blkid_probe pr, const struct befs_super_block *bs,
 				+ FS16_TO_CPU(sd->data_size, fs_le) + 1);
 
 	} while ((intptr_t) sd < (intptr_t) bi
-					+ FS32_TO_CPU(bi->inode_size, fs_le)
-					- sizeof(struct small_data));
+				+ (int32_t) FS32_TO_CPU(bi->inode_size, fs_le)
+				- (int32_t) sizeof(struct small_data));
 	if (*uuid == 0
 		&& (FS32_TO_CPU(bi->attributes.allocation_group, fs_le) != 0
 			|| FS16_TO_CPU(bi->attributes.start, fs_le) != 0
diff --git a/libblkid/src/superblocks/ddf_raid.c b/libblkid/src/superblocks/ddf_raid.c
index c0ba33517..24df421d1 100644
--- a/libblkid/src/superblocks/ddf_raid.c
+++ b/libblkid/src/superblocks/ddf_raid.c
@@ -71,10 +71,11 @@ struct ddf_header {
 	uint8_t		pad4[256];	/* 0xff */
 } __attribute__((packed));
 
-static int probe_ddf(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_ddf(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	int hdrs[] = { 1, 257 };
-	int i;
+	size_t i;
 	struct ddf_header *ddf = NULL;
 	char version[DDF_REV_LENGTH + 1];
 	uint64_t off, lba;
diff --git a/libblkid/src/superblocks/drbd.c b/libblkid/src/superblocks/drbd.c
index 3490948de..1e404069b 100644
--- a/libblkid/src/superblocks/drbd.c
+++ b/libblkid/src/superblocks/drbd.c
@@ -64,7 +64,8 @@ struct md_on_disk_08 {
 };
 
 
-static int probe_drbd(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_drbd(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct md_on_disk_08 *md;
 	off_t off;
diff --git a/libblkid/src/superblocks/ext.c b/libblkid/src/superblocks/ext.c
index 6dfe52831..4066347cd 100644
--- a/libblkid/src/superblocks/ext.c
+++ b/libblkid/src/superblocks/ext.c
@@ -311,7 +311,8 @@ static void ext_get_info(blkid_probe pr, int ver, struct ext2_super_block *es)
 }
 
 
-static int probe_jbd(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_jbd(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct ext2_super_block *es;
 	uint32_t fi;
@@ -326,7 +327,8 @@ static int probe_jbd(blkid_probe pr, const struct blkid_idmag *mag)
 	return 0;
 }
 
-static int probe_ext2(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_ext2(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct ext2_super_block *es;
 	uint32_t fc, frc, fi;
@@ -357,7 +359,8 @@ static int probe_ext2(blkid_probe pr, const struct blkid_idmag *mag)
 	return 0;
 }
 
-static int probe_ext3(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_ext3(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct ext2_super_block *es;
 	uint32_t fc, frc, fi;
@@ -380,7 +383,8 @@ static int probe_ext3(blkid_probe pr, const struct blkid_idmag *mag)
 }
 
 
-static int probe_ext4dev(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_ext4dev(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct ext2_super_block *es;
 	uint32_t fc, frc, fi;
@@ -425,7 +429,8 @@ force_ext4dev:
 	return 0;
 }
 
-static int probe_ext4(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_ext4(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct ext2_super_block *es;
 	uint32_t fc, frc, fi;
diff --git a/libblkid/src/superblocks/highpoint_raid.c b/libblkid/src/superblocks/highpoint_raid.c
index 25e3114b3..0b41344ae 100644
--- a/libblkid/src/superblocks/highpoint_raid.c
+++ b/libblkid/src/superblocks/highpoint_raid.c
@@ -22,7 +22,8 @@ struct hpt45x_metadata {
 #define HPT45X_MAGIC_OK			0x5a7816f3
 #define HPT45X_MAGIC_BAD		0x5a7816fd
 
-static int probe_highpoint45x(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_highpoint45x(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct hpt45x_metadata *hpt;
 	uint64_t off;
@@ -49,7 +50,8 @@ static int probe_highpoint45x(blkid_probe pr, const struct blkid_idmag *mag)
 	return 0;
 }
 
-static int probe_highpoint37x(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_highpoint37x(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	if (!S_ISREG(pr->mode) && !blkid_probe_is_wholedisk(pr))
 		return -1;
diff --git a/libblkid/src/superblocks/iso9660.c b/libblkid/src/superblocks/iso9660.c
index 9f3ce2e60..36bf07713 100644
--- a/libblkid/src/superblocks/iso9660.c
+++ b/libblkid/src/superblocks/iso9660.c
@@ -54,7 +54,7 @@ struct high_sierra_volume_descriptor {
 static int ascii_eq_utf16be(unsigned char *ascii,
 			unsigned char *utf16, size_t len)
 {
-	int a, u;
+	size_t a, u;
 
 	for (a = 0, u = 0; u < len; a++, u += 2) {
 		if (utf16[u] != 0x0 || ascii[a] != utf16[u + 1])
diff --git a/libblkid/src/superblocks/isw_raid.c b/libblkid/src/superblocks/isw_raid.c
index ac6251d7c..755c1b652 100644
--- a/libblkid/src/superblocks/isw_raid.c
+++ b/libblkid/src/superblocks/isw_raid.c
@@ -26,7 +26,8 @@ struct isw_metadata {
 #define ISW_SIGNATURE		"Intel Raid ISM Cfg Sig. "
 
 
-static int probe_iswraid(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_iswraid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	uint64_t off;
 	struct isw_metadata *isw;
diff --git a/libblkid/src/superblocks/jfs.c b/libblkid/src/superblocks/jfs.c
index 9a49c6746..78c018c15 100644
--- a/libblkid/src/superblocks/jfs.c
+++ b/libblkid/src/superblocks/jfs.c
@@ -41,9 +41,9 @@ static int probe_jfs(blkid_probe pr, const struct blkid_idmag *mag)
 	js = blkid_probe_get_sb(pr, mag, struct jfs_super_block);
 	if (!js)
 		return -1;
-	if (le32_to_cpu(js->js_bsize) != (1 << le16_to_cpu(js->js_l2bsize)))
+	if (le32_to_cpu(js->js_bsize) != (1U << le16_to_cpu(js->js_l2bsize)))
 		return 1;
-	if (le32_to_cpu(js->js_pbsize) != (1 << le16_to_cpu(js->js_l2pbsize)))
+	if (le32_to_cpu(js->js_pbsize) != (1U << le16_to_cpu(js->js_l2pbsize)))
 		return 1;
 	if ((le16_to_cpu(js->js_l2bsize) - le16_to_cpu(js->js_l2pbsize)) !=
 	    le16_to_cpu(js->js_l2bfactor))
diff --git a/libblkid/src/superblocks/jmicron_raid.c b/libblkid/src/superblocks/jmicron_raid.c
index d35b17f89..c7080780f 100644
--- a/libblkid/src/superblocks/jmicron_raid.c
+++ b/libblkid/src/superblocks/jmicron_raid.c
@@ -25,7 +25,8 @@ struct jm_metadata {
 
 #define JM_SIGNATURE		"JM"
 
-static int probe_jmraid(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_jmraid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	uint64_t off;
 	struct jm_metadata *jm;
diff --git a/libblkid/src/superblocks/linux_raid.c b/libblkid/src/superblocks/linux_raid.c
index e74f57de9..609d24bf7 100644
--- a/libblkid/src/superblocks/linux_raid.c
+++ b/libblkid/src/superblocks/linux_raid.c
@@ -148,11 +148,11 @@ static int probe_raid0(blkid_probe pr, blkid_loff_t off)
 
 	size <<= 10;	/* convert KiB to bytes */
 
-	if (pr->size < size + MD_RESERVED_BYTES)
+	if (pr->size < 0 || (uint64_t) pr->size < size + MD_RESERVED_BYTES)
 		/* device is too small */
 		return 1;
 
-	if (off < size)
+	if (off < 0 || (uint64_t) off < size)
 		/* no space before superblock */
 		return 1;
 
@@ -194,9 +194,9 @@ static int probe_raid1(blkid_probe pr, off_t off)
 		return -1;
 	if (le32_to_cpu(mdp1->magic) != MD_SB_MAGIC)
 		return -1;
-	if (le32_to_cpu(mdp1->major_version) != 1)
+	if (le32_to_cpu(mdp1->major_version) != 1U)
 		return -1;
-	if (le64_to_cpu(mdp1->super_offset) != off >> 9)
+	if (le64_to_cpu(mdp1->super_offset) != (uint64_t) off >> 9)
 		return -1;
 	if (blkid_probe_set_uuid(pr, (unsigned char *) mdp1->set_uuid) != 0)
 		return -1;
@@ -212,7 +212,8 @@ static int probe_raid1(blkid_probe pr, off_t off)
 	return 0;
 }
 
-int probe_raid(blkid_probe pr, const struct blkid_idmag *mag)
+int probe_raid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	const char *ver = NULL;
 
diff --git a/libblkid/src/superblocks/lsi_raid.c b/libblkid/src/superblocks/lsi_raid.c
index 5217a0093..56721dd71 100644
--- a/libblkid/src/superblocks/lsi_raid.c
+++ b/libblkid/src/superblocks/lsi_raid.c
@@ -23,7 +23,8 @@ struct lsi_metadata {
 
 #define LSI_SIGNATURE		"$XIDE$"
 
-static int probe_lsiraid(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_lsiraid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	uint64_t off;
 	struct lsi_metadata *lsi;
diff --git a/libblkid/src/superblocks/nvidia_raid.c b/libblkid/src/superblocks/nvidia_raid.c
index c3db949a8..dd86cdcc6 100644
--- a/libblkid/src/superblocks/nvidia_raid.c
+++ b/libblkid/src/superblocks/nvidia_raid.c
@@ -25,7 +25,8 @@ struct nv_metadata {
 
 #define NVIDIA_SIGNATURE		"NVIDIA"
 
-static int probe_nvraid(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_nvraid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	uint64_t off;
 	struct nv_metadata *nv;
diff --git a/libblkid/src/superblocks/promise_raid.c b/libblkid/src/superblocks/promise_raid.c
index 0e91d3c25..221146dbc 100644
--- a/libblkid/src/superblocks/promise_raid.c
+++ b/libblkid/src/superblocks/promise_raid.c
@@ -24,7 +24,8 @@ struct promise_metadata {
 #define PDC_CONFIG_OFF		0x1200
 #define PDC_SIGNATURE		"Promise Technology, Inc."
 
-static int probe_pdcraid(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_pdcraid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	unsigned int i;
 	static unsigned int sectors[] = {
diff --git a/libblkid/src/superblocks/silicon_raid.c b/libblkid/src/superblocks/silicon_raid.c
index b72b72760..fef58010c 100644
--- a/libblkid/src/superblocks/silicon_raid.c
+++ b/libblkid/src/superblocks/silicon_raid.c
@@ -41,7 +41,8 @@ struct silicon_metadata {
 #define SILICON_MAGIC		0x2F000000
 
 
-static int probe_silraid(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_silraid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	uint64_t off;
 	struct silicon_metadata *sil;
diff --git a/libblkid/src/superblocks/superblocks.c b/libblkid/src/superblocks/superblocks.c
index 9b618b28f..8a0edaa7c 100644
--- a/libblkid/src/superblocks/superblocks.c
+++ b/libblkid/src/superblocks/superblocks.c
@@ -251,7 +251,7 @@ int blkid_probe_filter_superblocks_usage(blkid_probe pr, int flag, int usage)
 {
 	unsigned long *fltr;
 	struct blkid_chain *chn;
-	int i;
+	size_t i;
 
 	if (!pr)
 		return -1;
@@ -283,7 +283,7 @@ int blkid_probe_filter_superblocks_usage(blkid_probe pr, int flag, int usage)
  */
 int blkid_known_fstype(const char *fstype)
 {
-	int i;
+	size_t i;
 
 	if (!fstype)
 		return 0;
@@ -306,7 +306,7 @@ int blkid_known_fstype(const char *fstype)
  */
 int blkid_superblocks_get_name(size_t idx, const char **name, int *usage)
 {
-	if (idx >= 0 && idx < ARRAY_SIZE(idinfos)) {
+	if (idx < ARRAY_SIZE(idinfos)) {
 		if (name)
 			*name = idinfos[idx]->name;
 		if (usage)
@@ -321,7 +321,7 @@ int blkid_superblocks_get_name(size_t idx, const char **name, int *usage)
  */
 static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
 {
-	int i = 0;
+	size_t i;
 
 	if (!pr || chn->idx < -1)
 		return -1;
@@ -337,7 +337,7 @@ static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
 		 * is 1 byte */
 		goto nothing;
 
-	i = chn->idx + 1;
+	i = chn->idx < 0 ? 0 : chn->idx + 1U;
 
 	for ( ; i < ARRAY_SIZE(idinfos); i++) {
 		const struct blkid_idinfo *id;
@@ -366,7 +366,7 @@ static int superblocks_probe(blkid_probe pr, struct blkid_chain *chn)
 		if ((id->usage & BLKID_USAGE_RAID) && blkid_probe_is_tiny(pr))
 			continue;
 
-		DBG(DEBUG_LOWPROBE, printf("[%d] %s:\n", i, id->name));
+		DBG(DEBUG_LOWPROBE, printf("[%zd] %s:\n", i, id->name));
 
 		if (blkid_probe_get_idmag(pr, id, &off, &mag))
 			continue;
@@ -593,7 +593,7 @@ int blkid_probe_set_utf8label(blkid_probe pr, unsigned char *label,
 /* like uuid_is_null() from libuuid, but works with arbitrary size of UUID */
 static int uuid_is_empty(const unsigned char *buf, size_t len)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < len; i++)
 		if (buf[i])
@@ -626,7 +626,7 @@ int blkid_probe_sprintf_uuid(blkid_probe pr, unsigned char *uuid,
 
 	/* convert to lower case (..be paranoid) */
 	if (!rc) {
-		int i;
+		size_t i;
 		struct blkid_prval *v = __blkid_probe_get_value(pr,
 						blkid_probe_numof_values(pr));
 		if (v) {
diff --git a/libblkid/src/superblocks/sysv.c b/libblkid/src/superblocks/sysv.c
index 00c8c978b..80b0cc542 100644
--- a/libblkid/src/superblocks/sysv.c
+++ b/libblkid/src/superblocks/sysv.c
@@ -90,11 +90,12 @@ static int probe_xenix(blkid_probe pr, const struct blkid_idmag *mag)
 /* Note that we don't probe for Coherent FS, this FS does not have
  * magic string. (It requires to probe fname/fpack field..)
  */
-static int probe_sysv(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_sysv(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct sysv_super_block *sb;
 	int blocks[] = {0, 9, 15, 18};
-	int i;
+	size_t i;
 
 	for (i = 0; i < ARRAY_SIZE(blocks); i++) {
 		int off = blocks[i] * SYSV_BLOCK_SIZE + SYSV_BLOCK_SIZE/2;
diff --git a/libblkid/src/superblocks/udf.c b/libblkid/src/superblocks/udf.c
index 766d6980f..a5afc5c58 100644
--- a/libblkid/src/superblocks/udf.c
+++ b/libblkid/src/superblocks/udf.c
@@ -57,7 +57,8 @@ struct volume_structure_descriptor {
 
 #define UDF_VSD_OFFSET			0x8000LL
 
-static int probe_udf(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_udf(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	struct volume_descriptor *vd;
 	struct volume_structure_descriptor *vsd;
diff --git a/libblkid/src/superblocks/ufs.c b/libblkid/src/superblocks/ufs.c
index 05bed1451..3ace715e9 100644
--- a/libblkid/src/superblocks/ufs.c
+++ b/libblkid/src/superblocks/ufs.c
@@ -163,20 +163,21 @@ struct ufs_super_block {
 #define UFS_MAGIC_SEC			0x00612195
 #define UFS_MAGIC_4GB			0x05231994
 
-static int probe_ufs(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_ufs(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	int offsets[] = { 0, 8, 64, 256 };
-	int mags[] = {
+	uint32_t mags[] = {
 		UFS2_MAGIC, UFS_MAGIC, UFS_MAGIC_FEA, UFS_MAGIC_LFN,
 		UFS_MAGIC_SEC, UFS_MAGIC_4GB
 	};
-	int i;
+	size_t i;
 	uint32_t magic;
 	struct ufs_super_block *ufs;
 
 	for (i = 0; i < ARRAY_SIZE(offsets); i++) {
 		uint32_t magLE, magBE;
-		int y;
+		size_t y;
 
 		ufs = (struct ufs_super_block *)
 				blkid_probe_get_buffer(pr,
diff --git a/libblkid/src/superblocks/vfat.c b/libblkid/src/superblocks/vfat.c
index bf474630d..13d576953 100644
--- a/libblkid/src/superblocks/vfat.c
+++ b/libblkid/src/superblocks/vfat.c
@@ -121,7 +121,7 @@ static unsigned char *search_fat_label(blkid_probe pr,
 				uint64_t offset, uint32_t entries)
 {
 	struct vfat_dir_entry *ent, *dir = NULL;
-	int i;
+	uint32_t i;
 
 	DBG(DEBUG_LOWPROBE,
 		printf("\tlook for label in root-dir "
diff --git a/libblkid/src/superblocks/via_raid.c b/libblkid/src/superblocks/via_raid.c
index 201313801..eba7e4bf2 100644
--- a/libblkid/src/superblocks/via_raid.c
+++ b/libblkid/src/superblocks/via_raid.c
@@ -45,7 +45,8 @@ static uint8_t via_checksum(struct via_metadata *v)
 	return cs == v->checksum;
 }
 
-static int probe_viaraid(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_viaraid(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	uint64_t off;
 	struct via_metadata *v;
diff --git a/libblkid/src/superblocks/zfs.c b/libblkid/src/superblocks/zfs.c
index af5264d46..b96c5df45 100644
--- a/libblkid/src/superblocks/zfs.c
+++ b/libblkid/src/superblocks/zfs.c
@@ -70,7 +70,7 @@ static void zfs_extract_guid_name(blkid_probe pr, loff_t offset)
 {
 	struct nvlist *nvl;
 	struct nvpair *nvp;
-	int left = 4096;
+	size_t left = 4096;
 	int found = 0;
 
 	offset = (offset & ~(VDEV_LABEL_SIZE - 1)) + VDEV_LABEL_NVPAIR;
@@ -94,7 +94,7 @@ static void zfs_extract_guid_name(blkid_probe pr, loff_t offset)
 		nvp->nvp_namelen = be32_to_cpu(nvp->nvp_namelen);
 		avail = nvp->nvp_size - nvp->nvp_namelen - sizeof(*nvp);
 
-		nvdebug("left %u, nvp_size %u\n", left, nvp->nvp_size);
+		nvdebug("left %zd nvp_size %u\n", left, nvp->nvp_size);
 		if (left < nvp->nvp_size || avail < 0)
 			break;
 
@@ -148,7 +148,10 @@ static void zfs_extract_guid_name(blkid_probe pr, loff_t offset)
 							 "%"PRIu64, nvu_value);
 			found++;
 		}
-		left -= nvp->nvp_size;
+		if (left > nvp->nvp_size)
+			left -= nvp->nvp_size;
+		else
+			left = 0;
 		nvp = (struct nvpair *)((char *)nvp + nvp->nvp_size);
 	}
 }
@@ -159,7 +162,8 @@ static void zfs_extract_guid_name(blkid_probe pr, loff_t offset)
 /* ZFS has 128x1kB host-endian root blocks, stored in 2 areas at the start
  * of the disk, and 2 areas at the end of the disk.  Check only some of them...
  * #4 (@ 132kB) is the first one written on a new filesystem. */
-static int probe_zfs(blkid_probe pr, const struct blkid_idmag *mag)
+static int probe_zfs(blkid_probe pr,
+		const struct blkid_idmag *mag __attribute__((__unused__)))
 {
 	uint64_t swab_magic = swab64(UBERBLOCK_MAGIC);
 	struct zfs_uberblock *ub;