more -Wall warning fixes from Cristian Ionescu-Idbohrn.

This time it resulted in small code changes:

function                                             old     new   delta
nexpr                                                820     828      +8
tail_main                                           1200    1202      +2
wrapf                                                166     167      +1
parse_mount_options                                  227     209     -18
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/1 up/down: 11/-18)             Total: -7 bytes

libbb/lineedit.c

@@ -262,7 +262,7 @@ static void input_backward(unsigned num)
 		return;
 	cursor -= num;
 
-	if (cmdedit_x >= num) {
+	if ((unsigned)cmdedit_x >= num) {
 		cmdedit_x -= num;
 		if (num <= 4) {
 			/* This is longer by 5 bytes on x86.
@@ -321,7 +321,7 @@ static void input_delete(int save)
 {
 	int j = cursor;
 
-	if (j == command_len)
+	if (j == (int)command_len)
 		return;
 
 #if ENABLE_FEATURE_EDITING_VI
@@ -830,7 +830,7 @@ static void input_tab(smallint *lastWasTab)
 
 	if (!*lastWasTab) {
 		char *tmp, *tmp1;
-		int len_found;
+		size_t len_found;
 /*		char matchBuf[MAX_LINELEN]; */
 #define matchBuf (S.input_tab__matchBuf)
 		int find_type;
@@ -1787,7 +1787,7 @@ int read_line_input(const char *prompt, char *command, int maxsize, line_input_t
 			if (vi_cmdmode)  /* Don't self-insert */
 				break;
 #endif
-			if (command_len >= (maxsize - 2))        /* Need to leave space for enter */
+			if ((int)command_len >= (maxsize - 2))        /* Need to leave space for enter */
 				break;
 
 			command_len++;

libbb/md5.c

@@ -383,7 +383,7 @@ void md5_hash(const void *buffer, size_t len, md5_ctx_t *ctx)
 	// Process all input.
 
 	while (len) {
-		int i = 64 - ctx->buflen;
+		unsigned i = 64 - ctx->buflen;
 
 		// Copy data into aligned buffer.
 

libbb/read.c

@@ -111,7 +111,7 @@ void xread(int fd, void *buf, size_t count)
 {
 	if (count) {
 		ssize_t size = full_read(fd, buf, count);
-		if (size != count)
+		if ((size_t)size != count)
 			bb_error_msg_and_die("short read");
 	}
 }
@@ -160,7 +160,7 @@ char *xmalloc_reads(int fd, char *buf, size_t *maxsz_p)
 
 	goto jump_in;
 	while (sz < maxsz) {
-		if (p - buf == sz) {
+		if ((size_t)(p - buf) == sz) {
  jump_in:
 			buf = xrealloc(buf, sz + 128);
 			p = buf + sz;

libbb/u_signal_names.c

@@ -130,7 +130,7 @@ int get_signum(const char *name)
 		return i;
 	if (strncasecmp(name, "SIG", 3) == 0)
 		name += 3;
-	for (i = 0; i < ARRAY_SIZE(signals); i++)
+	for (i = 0; (size_t)i < ARRAY_SIZE(signals); i++)
 		if (strcasecmp(name, signals[i]) == 0)
 			return i;
 
@@ -172,7 +172,7 @@ void print_signames(void)
 {
 	int signo;
 
-	for (signo = 1; signo < ARRAY_SIZE(signals); signo++) {
+	for (signo = 1; (size_t)signo < ARRAY_SIZE(signals); signo++) {
 		const char *name = signals[signo];
 		if (name[0])
 			puts(name);

libbb/xfuncs_printf.c

@@ -204,7 +204,7 @@ void xwrite(int fd, const void *buf, size_t count)
 {
 	if (count) {
 		ssize_t size = full_write(fd, buf, count);
-		if (size != count)
+		if ((size_t)size != count)
 			bb_error_msg_and_die("short write");
 	}
 }