From 3ed5d021837768405d9f9c9e7d2b05dc6a110d94 Mon Sep 17 00:00:00 2001
From: "Dmitry V. Levin" <ldv@altlinux.org>
Date: Wed, 10 Sep 2014 13:46:04 +0000
Subject: [PATCH] Fix compilation warnings reported by gcc -Wsign-compare

* configure.ac (gl_WARN_ADD): Add -Wsign-compare.
* defs.h (struct tcb): Change 'currpers' type to unsigned.
(struct xlat): Change 'val' type to unsigned
(signame): Add 'const' qualifier to its argument.
(xlookup, printxval): Add 'const' qualifier to the 2nd argument and
change its type to unsigned.
(printpathn): Change the 3rd argument type to unsigned.
(ioctl_lookup): Change 1st argument type to unsigned.
* count.c (call_summary_pers, call_summary): Change 'i' type to unsigned.
* file.c (print_xattr_list): Fix comparisons between signed and unsigned
long values.
* ioctl.c (compare): Fix cast.
(ioctl_lookup): Change 1st argument type to to unsigned.
(ioctl_next_match): Change 'code' type to unsigned.
* mem.c (sys_move_pages): Change 'i' type to unsigned.
* mtd.c (mtd_ioctl): Change 'i' and 'j' types to unsigned.
Print 'i' using %u format string.
* process.c (sys_prctl): Change 'i' type to unsigned.
(printargv): Change 'n' type to unsigned.
(sys_ptrace): Change 'addr' type to unsigned.
* scsi.c (print_sg_io_buffer): Add 'const' qualifier to 'len' argument
and change its type to unsigned.  Change 'i' and 'allocated' types
to unsigned.
* signal.c (signame): Add 'const' qualifier to its argument.
Fix comparisons between signed and unsigned values.
(sprintsigmask_n, printsiginfo): Fix comparisons between signed and
unsigned values.
* sock.c (sock_ioctl): Change 'i' and 'nifra' types to unsigned.
* strace.c (expand_tcbtab, alloctcb): Change 'i' type to unsigned.
(detach): Change 'sig' type to unsigned.
(startup_attach): Change 'tcbi' type to unsigned.
(startup_child): Change 'm', 'n', and 'len' types to unsigned.
(init): Use new variable to iterate 'tcbtab'.
(pid2tcb): Change 'i' type to unsigned.
(cleanup): Change 'i' and 'sig' types to unsigned.
* syscall.c (update_personality): Change 'personality' argument type
to unsigned.
(struct qual_options): Change 'bitflag' type to unsigned.
(reallocate_qual): Add 'const' qualifier to its argument and change its
type to unsigned.
(qualify_one): Change 'n' and 'bitflag' arguments types to unsigned.
Add 'const' qualifier to 'n', 'not', and 'pers' arguments.
Change 'p' type to signed int.
(qual_syscall): Change 'bitflag' argument type to unsigned.
Add 'const' qualifier to 'bitflag' and 'not' arguments.
Change 'p' type to signed int.
(qual_signal): Change 'bitflag' argument type to unsigned.
Add 'const' qualifier to 'bitflag' and 'not' arguments.
Change 'i' type to unsigned.
(qual_desc): Change 'bitflag' argument type to unsigned.
Add 'const' qualifier to 'bitflag' and 'not' arguments.
(qualify): Change 'i' type to unsigned.
(get_scno): Change 'currpers' type to unsigned.
Fix a comparison between signed and unsigned values.
* system.c (sys_sysctl): Change 'cnt' and 'max_cnt' types to unsigned.
Fix comparisons between signed and unsigned values.
* util.c (xlookup, printxval): Add 'const' qualifier to 'val' argument
and change its type to unsigned.
(printuid): Fix a comparison between signed and unsigned values.
(printpathn): Change 'n' argument type to unsigned.
(printstr): Change 'size' type to unsigned.
Fix a comparison between signed and unsigned values.
(setbpt): Change 'i' type to unsigned.
* net.c (printsock): Silence a compilation warning.
* reboot.c (sys_reboot): Likewise.
---
 configure.ac |  1 +
 count.c      |  4 ++--
 defs.h       | 14 +++++++-------
 file.c       |  3 ++-
 ioctl.c      |  6 +++---
 mem.c        |  6 +++---
 mtd.c        |  4 ++--
 net.c        |  2 +-
 process.c    |  6 +++---
 reboot.c     |  2 +-
 scsi.c       |  7 +++----
 signal.c     | 24 ++++++++++++++----------
 sock.c       |  4 ++--
 strace.c     | 28 +++++++++++++++-------------
 syscall.c    | 41 +++++++++++++++++++++--------------------
 system.c     |  6 +++---
 util.c       | 14 +++++++-------
 17 files changed, 90 insertions(+), 82 deletions(-)

diff --git a/configure.ac b/configure.ac
index 52c1ecf6..6fe83cfb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -164,6 +164,7 @@ AC_DEFINE_UNQUOTED([ENABLE_ARM_OABI], [$enable_arm_oabi],
 
 gl_WARN_ADD([-Wall])
 gl_WARN_ADD([-Wwrite-strings])
+gl_WARN_ADD([-Wsign-compare])
 AC_ARG_ENABLE([gcc-Werror],
   [AS_HELP_STRING([--enable-gcc-Werror], [turn on gcc's -Werror option])],
   [case $enableval in
diff --git a/count.c b/count.c
index e41994d3..25921b25 100644
--- a/count.c
+++ b/count.c
@@ -156,7 +156,7 @@ void set_overhead(int n)
 static void
 call_summary_pers(FILE *outf)
 {
-	int     i;
+	unsigned int i;
 	int     call_cum, error_cum;
 	struct timeval tv_cum, dtv;
 	double  float_tv_cum;
@@ -230,7 +230,7 @@ call_summary_pers(FILE *outf)
 void
 call_summary(FILE *outf)
 {
-	int i, old_pers = current_personality;
+	unsigned int i, old_pers = current_personality;
 
 	for (i = 0; i < SUPPORTED_PERSONALITIES; ++i) {
 		if (!countv[i])
diff --git a/defs.h b/defs.h
index 625cac67..396e5196 100644
--- a/defs.h
+++ b/defs.h
@@ -414,7 +414,7 @@ struct tcb {
 #endif
 	long u_rval;		/* Return value */
 #if SUPPORTED_PERSONALITIES > 1
-	int currpers;		/* Personality at the time of scno update */
+	unsigned int currpers;	/* Personality at the time of scno update */
 #endif
 	int curcol;		/* Output column for this process */
 	FILE *outf;		/* Output file for this process */
@@ -508,7 +508,7 @@ typedef uint8_t qualbits_t;
 #define filtered(tcp)	((tcp)->flags & TCB_FILTERED)
 
 struct xlat {
-	int val;
+	unsigned int val;
 	const char *str;
 };
 #define XLAT(x) { x, #x }
@@ -642,12 +642,12 @@ extern long getrval2(struct tcb *);
 extern int setbpt(struct tcb *);
 extern int clearbpt(struct tcb *);
 
-extern const char *signame(int);
+extern const char *signame(const int);
 extern void pathtrace_select(const char *);
 extern int pathtrace_match(struct tcb *);
 extern int getfdpath(struct tcb *, int, char *, unsigned);
 
-extern const char *xlookup(const struct xlat *, int);
+extern const char *xlookup(const struct xlat *, const unsigned int);
 
 extern int string_to_uint(const char *str);
 extern int string_quote(const char *, char *, long, int);
@@ -665,7 +665,7 @@ extern int next_set_bit(const void *bit_array, unsigned cur_bit, unsigned size_b
 #endif
 extern int printllval(struct tcb *, const char *, int);
 
-extern void printxval(const struct xlat *, int, const char *);
+extern void printxval(const struct xlat *, const unsigned int, const char *);
 extern int printargs(struct tcb *);
 extern int printargs_lu(struct tcb *);
 extern int printargs_ld(struct tcb *);
@@ -678,7 +678,7 @@ extern void printstr(struct tcb *, long, long);
 extern void printnum(struct tcb *, long, const char *);
 extern void printnum_int(struct tcb *, long, const char *);
 extern void printpath(struct tcb *, long);
-extern void printpathn(struct tcb *, long, int);
+extern void printpathn(struct tcb *, long, unsigned int);
 #define TIMESPEC_TEXT_BUFSIZE (sizeof(long)*3 * 2 + sizeof("{%u, %u}"))
 #define TIMEVAL_TEXT_BUFSIZE  TIMESPEC_TEXT_BUFSIZE
 extern void printtv_bitness(struct tcb *, long, enum bitness_t, int);
@@ -710,7 +710,7 @@ extern void tprint_open_modes(mode_t);
 extern const char *sprint_open_modes(mode_t);
 extern void print_loff_t(struct tcb *, long);
 
-extern const struct_ioctlent *ioctl_lookup(long);
+extern const struct_ioctlent *ioctl_lookup(unsigned long);
 extern const struct_ioctlent *ioctl_next_match(const struct_ioctlent *);
 extern int ioctl_decode(struct tcb *, long, long);
 extern int term_ioctl(struct tcb *, long, long);
diff --git a/file.c b/file.c
index 47ca2302..f788bd69 100644
--- a/file.c
+++ b/file.c
@@ -2202,7 +2202,8 @@ print_xattr_list(struct tcb *tcp, unsigned long addr, unsigned long size)
 			tprints("NULL");
 		} else {
 			unsigned long len =
-				(size < tcp->u_rval) ? size : tcp->u_rval;
+				(size < (unsigned long) tcp->u_rval) ?
+					size : (unsigned long) tcp->u_rval;
 			printstr(tcp, addr, len);
 		}
 	}
diff --git a/ioctl.c b/ioctl.c
index 3f6c410b..99b31fb0 100644
--- a/ioctl.c
+++ b/ioctl.c
@@ -34,13 +34,13 @@
 static int
 compare(const void *a, const void *b)
 {
-	unsigned long code1 = (long) a;
+	unsigned long code1 = (unsigned long) a;
 	unsigned long code2 = ((struct_ioctlent *) b)->code;
 	return (code1 > code2) ? 1 : (code1 < code2) ? -1 : 0;
 }
 
 const struct_ioctlent *
-ioctl_lookup(long code)
+ioctl_lookup(unsigned long code)
 {
 	struct_ioctlent *iop;
 
@@ -60,7 +60,7 @@ ioctl_lookup(long code)
 const struct_ioctlent *
 ioctl_next_match(const struct_ioctlent *iop)
 {
-	long code;
+	unsigned long code;
 
 	code = iop->code;
 	iop++;
diff --git a/mem.c b/mem.c
index 6ecd363c..28f744fb 100644
--- a/mem.c
+++ b/mem.c
@@ -481,7 +481,7 @@ sys_move_pages(struct tcb *tcp)
 		if (tcp->u_arg[2] == 0)
 			tprints("NULL, ");
 		else {
-			int i;
+			unsigned int i;
 			long puser = tcp->u_arg[2];
 			tprints("{");
 			for (i = 0; i < npages; ++i) {
@@ -500,7 +500,7 @@ sys_move_pages(struct tcb *tcp)
 		if (tcp->u_arg[3] == 0)
 			tprints("NULL, ");
 		else {
-			int i;
+			unsigned int i;
 			long nodeuser = tcp->u_arg[3];
 			tprints("{");
 			for (i = 0; i < npages; ++i) {
@@ -522,7 +522,7 @@ sys_move_pages(struct tcb *tcp)
 		if (tcp->u_arg[4] == 0)
 			tprints("NULL, ");
 		else {
-			int i;
+			unsigned int i;
 			long statususer = tcp->u_arg[4];
 			tprints("{");
 			for (i = 0; i < npages; ++i) {
diff --git a/mtd.c b/mtd.c
index 8ba658b5..88e8dbcc 100644
--- a/mtd.c
+++ b/mtd.c
@@ -60,7 +60,7 @@ int mtd_ioctl(struct tcb *tcp, long code, long arg)
 	struct mtd_write_req mreq;
 	struct nand_oobinfo ninfo;
 	struct nand_ecclayout_user nlay;
-	int i, j;
+	unsigned int i, j;
 
 	if (entering(tcp))
 		return 0;
@@ -235,7 +235,7 @@ int mtd_ioctl(struct tcb *tcp, long code, long arg)
 		if (!verbose(tcp) || umove(tcp, arg, &i) < 0)
 			return 0;
 
-		tprintf(", [%d]", i);
+		tprintf(", [%u]", i);
 		return 1;
 
 	case MTDFILEMODE:
diff --git a/net.c b/net.c
index 7b899170..46c491f8 100644
--- a/net.c
+++ b/net.c
@@ -189,7 +189,7 @@ printsock(struct tcb *tcp, long addr, int addrlen)
 		return;
 	}
 
-	if (addrlen < 2 || addrlen > sizeof(addrbuf))
+	if (addrlen < 2 || addrlen > (int) sizeof(addrbuf))
 		addrlen = sizeof(addrbuf);
 
 	memset(&addrbuf, 0, sizeof(addrbuf));
diff --git a/process.c b/process.c
index 2cd0f01f..e465319e 100644
--- a/process.c
+++ b/process.c
@@ -131,7 +131,7 @@ unalignctl_string(unsigned int ctl)
 int
 sys_prctl(struct tcb *tcp)
 {
-	int i;
+	unsigned int i;
 
 	if (entering(tcp)) {
 		printxval(prctl_options, tcp->u_arg[0], "PR_???");
@@ -726,7 +726,7 @@ printargv(struct tcb *tcp, long addr)
 		char data[sizeof(long)];
 	} cp;
 	const char *sep;
-	int n = 0;
+	unsigned int n = 0;
 	unsigned wordsize = current_wordsize;
 
 	cp.p64 = 1;
@@ -2103,7 +2103,7 @@ int
 sys_ptrace(struct tcb *tcp)
 {
 	const struct xlat *x;
-	long addr;
+	unsigned long addr;
 
 	if (entering(tcp)) {
 		printxval(ptrace_cmds, tcp->u_arg[0], "PTRACE_???");
diff --git a/reboot.c b/reboot.c
index 397a1269..e3fa77a9 100644
--- a/reboot.c
+++ b/reboot.c
@@ -16,7 +16,7 @@ sys_reboot(struct tcb *tcp)
 	printflags(bootflags2, tcp->u_arg[1], "LINUX_REBOOT_MAGIC_???");
 	tprints(", ");
 	printflags(bootflags3, tcp->u_arg[2], "LINUX_REBOOT_CMD_???");
-	if (tcp->u_arg[2] == LINUX_REBOOT_CMD_RESTART2) {
+	if (tcp->u_arg[2] == (long) LINUX_REBOOT_CMD_RESTART2) {
 		tprints(", ");
 		printstr(tcp, tcp->u_arg[3], -1);
 	}
diff --git a/scsi.c b/scsi.c
index 2aa4c7b3..a2e23c8b 100644
--- a/scsi.c
+++ b/scsi.c
@@ -36,16 +36,15 @@
 #include "xlat/sg_io_dxfer_direction.h"
 
 static void
-print_sg_io_buffer(struct tcb *tcp, unsigned char *addr, int len)
+print_sg_io_buffer(struct tcb *tcp, unsigned char *addr, const unsigned int len)
 {
 	unsigned char *buf = NULL;
-	int     allocated, i;
+	unsigned int allocated, i;
 
 	if (len == 0)
 		return;
 	allocated = (len > max_strlen) ? max_strlen : len;
-	if (len < 0 ||
-	    (buf = malloc(allocated)) == NULL ||
+	if ((buf = malloc(allocated)) == NULL ||
 	    umoven(tcp, (unsigned long) addr, allocated, (char *) buf) < 0) {
 		tprintf("%p", addr);
 		free(buf);
diff --git a/signal.c b/signal.c
index f6eeed0e..74e0fd90 100644
--- a/signal.c
+++ b/signal.c
@@ -144,18 +144,22 @@ struct sigcontext {
  */
 
 const char *
-signame(int sig)
+signame(const int sig)
 {
-	static char buf[sizeof("SIGRT_%d") + sizeof(int)*3];
+	static char buf[sizeof("SIGRT_%u") + sizeof(int)*3];
 
-	if (sig >= 0 && sig < nsignals)
-		return signalent[sig];
+	if (sig >= 0) {
+		const unsigned int s = sig;
+
+		if (s < nsignals)
+			return signalent[s];
 #ifdef SIGRTMIN
-	if (sig >= __SIGRTMIN && sig <= __SIGRTMAX) {
-		sprintf(buf, "SIGRT_%d", (int)(sig - __SIGRTMIN));
-		return buf;
-	}
+		if (s >= __SIGRTMIN && s <= __SIGRTMAX) {
+			sprintf(buf, "SIGRT_%u", s - __SIGRTMIN);
+			return buf;
+		}
 #endif
+	}
 	sprintf(buf, "%d", sig);
 	return buf;
 }
@@ -217,7 +221,7 @@ sprintsigmask_n(const char *prefix, const void *sig_mask, unsigned int bytes)
 	for (i = 0; (i = next_set_bit(mask, i, size * 32)) >= 0; ) {
 		++i;
 		*s++ = sep;
-		if (i < nsignals) {
+		if ((unsigned) i < nsignals) {
 			s = stpcpy(s, signalent[i] + 3);
 		}
 #ifdef SIGRTMIN
@@ -428,7 +432,7 @@ printsiginfo(siginfo_t *sip, int verbose)
 #endif
 	{
 		if (sip->si_errno) {
-			if (sip->si_errno < 0 || sip->si_errno >= nerrnos)
+			if (sip->si_errno < 0 || (unsigned) sip->si_errno >= nerrnos)
 				tprintf(", si_errno=%d", sip->si_errno);
 			else
 				tprintf(", si_errno=%s",
diff --git a/sock.c b/sock.c
index d3a5b35a..dca9bfd4 100644
--- a/sock.c
+++ b/sock.c
@@ -224,8 +224,8 @@ sock_ioctl(struct tcb *tcp, long code, long arg)
 		} else if (ifc.ifc_buf == NULL) {
 			tprints("NULL");
 		} else {
-			int i;
-			unsigned nifra = ifc.ifc_len / sizeof(struct ifreq);
+			unsigned int i;
+			unsigned int nifra = ifc.ifc_len / sizeof(struct ifreq);
 			struct ifreq ifra[nifra];
 
 			if (umoven(tcp, (unsigned long) ifc.ifc_buf,
diff --git a/strace.c b/strace.c
index 2bc5c675..0ef44aa1 100644
--- a/strace.c
+++ b/strace.c
@@ -675,7 +675,7 @@ expand_tcbtab(void)
 	   callers have pointers and it would be a pain.
 	   So tcbtab is a table of pointers.  Since we never
 	   free the TCBs, we allocate a single chunk of many.  */
-	int i = tcbtabsize;
+	unsigned int i = tcbtabsize;
 	struct tcb *newtcbs = calloc(tcbtabsize, sizeof(newtcbs[0]));
 	struct tcb **newtab = realloc(tcbtab, tcbtabsize * 2 * sizeof(tcbtab[0]));
 	if (!newtab || !newtcbs)
@@ -689,7 +689,7 @@ expand_tcbtab(void)
 static struct tcb *
 alloctcb(int pid)
 {
-	int i;
+	unsigned int i;
 	struct tcb *tcp;
 
 	if (nprocs == tcbtabsize)
@@ -837,7 +837,7 @@ detach(struct tcb *tcp)
 	 * 3. Attach SIGSTOP was already pending (TCB_IGNORE_ONE_SIGSTOP set)
 	 */
 	for (;;) {
-		int sig;
+		unsigned int sig;
 		if (waitpid(tcp->pid, &status, __WALL) < 0) {
 			if (errno == EINTR)
 				continue;
@@ -954,7 +954,7 @@ process_opt_p_list(char *opt)
 static void
 startup_attach(void)
 {
-	int tcbi;
+	unsigned int tcbi;
 	struct tcb *tcp;
 
 	/*
@@ -1183,7 +1183,7 @@ startup_child(char **argv)
 #endif /* USE_DEBUGGING_EXEC */
 	else {
 		const char *path;
-		int m, n, len;
+		size_t m, n, len;
 
 		for (path = getenv("PATH"); path && *path; path += m) {
 			const char *colon = strchr(path, ':');
@@ -1635,6 +1635,7 @@ init(int argc, char *argv[])
 	struct tcb *tcp;
 	int c, i;
 	int optF = 0;
+	unsigned int tcbi;
 	struct sigaction sa;
 
 	progname = argv[0] ? argv[0] : "strace";
@@ -1658,8 +1659,8 @@ init(int argc, char *argv[])
 	tcp = calloc(tcbtabsize, sizeof(*tcp));
 	if (!tcp)
 		die_out_of_memory();
-	for (c = 0; c < tcbtabsize; c++)
-		tcbtab[c] = tcp++;
+	for (tcbi = 0; tcbi < tcbtabsize; tcbi++)
+		tcbtab[tcbi] = tcp++;
 
 	shared_log = stderr;
 	set_sortby(DEFAULT_SORTBY);
@@ -1978,7 +1979,7 @@ init(int argc, char *argv[])
 static struct tcb *
 pid2tcb(int pid)
 {
-	int i;
+	unsigned int i;
 
 	if (pid <= 0)
 		return NULL;
@@ -1995,7 +1996,7 @@ pid2tcb(int pid)
 static void
 cleanup(void)
 {
-	int i;
+	unsigned int i;
 	struct tcb *tcp;
 	int fatal_sig;
 
@@ -2049,10 +2050,11 @@ trace(void)
 	while (1) {
 		int pid;
 		int wait_errno;
-		int status, sig;
+		int status;
 		int stopped;
-		struct tcb *tcp;
+		unsigned int sig;
 		unsigned event;
+		struct tcb *tcp;
 
 		if (interrupted)
 			return;
@@ -2185,10 +2187,10 @@ trace(void)
 			if (ptrace(PTRACE_GETEVENTMSG, pid, NULL, (long) &old_pid) < 0)
 				goto dont_switch_tcbs;
 			/* Avoid truncation in pid2tcb() param passing */
-			if (old_pid > UINT_MAX)
-				goto dont_switch_tcbs;
 			if (old_pid <= 0 || old_pid == pid)
 				goto dont_switch_tcbs;
+			if ((unsigned long) old_pid > UINT_MAX)
+				goto dont_switch_tcbs;
 			execve_thread = pid2tcb(old_pid);
 			/* It should be !NULL, but I feel paranoid */
 			if (!execve_thread)
diff --git a/syscall.c b/syscall.c
index b0ad47e1..e74881d5 100644
--- a/syscall.c
+++ b/syscall.c
@@ -323,7 +323,7 @@ set_personality(int personality)
 }
 
 static void
-update_personality(struct tcb *tcp, int personality)
+update_personality(struct tcb *tcp, unsigned int personality)
 {
 	if (personality == current_personality)
 		return;
@@ -370,7 +370,7 @@ update_personality(struct tcb *tcp, int personality)
 static int qual_syscall(), qual_signal(), qual_desc();
 
 static const struct qual_options {
-	int bitflag;
+	unsigned int bitflag;
 	const char *option_name;
 	int (*qualify)(const char *, int, int);
 	const char *argument_name;
@@ -396,7 +396,7 @@ static const struct qual_options {
 };
 
 static void
-reallocate_qual(int n)
+reallocate_qual(const unsigned int n)
 {
 	unsigned p;
 	qualbits_t *qp;
@@ -410,9 +410,9 @@ reallocate_qual(int n)
 }
 
 static void
-qualify_one(int n, int bitflag, int not, int pers)
+qualify_one(const unsigned int n, unsigned int bitflag, const int not, const int pers)
 {
-	unsigned p;
+	int p;
 
 	if (num_quals <= n)
 		reallocate_qual(n + 1);
@@ -428,10 +428,10 @@ qualify_one(int n, int bitflag, int not, int pers)
 }
 
 static int
-qual_syscall(const char *s, int bitflag, int not)
+qual_syscall(const char *s, const unsigned int bitflag, const int not)
 {
-	unsigned p;
-	unsigned i;
+	int p;
+	unsigned int i;
 	int rc = -1;
 
 	if (*s >= '0' && *s <= '9') {
@@ -457,9 +457,9 @@ qual_syscall(const char *s, int bitflag, int not)
 }
 
 static int
-qual_signal(const char *s, int bitflag, int not)
+qual_signal(const char *s, const unsigned int bitflag, const int not)
 {
-	int i;
+	unsigned int i;
 
 	if (*s >= '0' && *s <= '9') {
 		int signo = string_to_uint(s);
@@ -480,7 +480,7 @@ qual_signal(const char *s, int bitflag, int not)
 }
 
 static int
-qual_desc(const char *s, int bitflag, int not)
+qual_desc(const char *s, const unsigned int bitflag, const int not)
 {
 	if (*s >= '0' && *s <= '9') {
 		int desc = string_to_uint(s);
@@ -516,20 +516,20 @@ void
 qualify(const char *s)
 {
 	const struct qual_options *opt;
-	int not;
 	char *copy;
 	const char *p;
-	int i, n;
+	int not;
+	unsigned int i;
 
 	if (num_quals == 0)
 		reallocate_qual(MIN_QUALS);
 
 	opt = &qual_options[0];
 	for (i = 0; (p = qual_options[i].option_name); i++) {
-		n = strlen(p);
-		if (strncmp(s, p, n) == 0 && s[n] == '=') {
+		unsigned int len = strlen(p);
+		if (strncmp(s, p, len) == 0 && s[len] == '=') {
 			opt = &qual_options[i];
-			s += n + 1;
+			s += len + 1;
 			break;
 		}
 	}
@@ -555,6 +555,7 @@ qualify(const char *s)
 	if (!copy)
 		die_out_of_memory();
 	for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
+		int n;
 		if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
 			unsigned pers;
 			for (pers = 0; pers < SUPPORTED_PERSONALITIES; pers++) {
@@ -1220,7 +1221,7 @@ get_scno(struct tcb *tcp)
 #elif defined(POWERPC)
 	scno = ppc_regs.gpr[0];
 # ifdef POWERPC64
-	int currpers;
+	unsigned int currpers;
 
 	/*
 	 * Check for 64/32 bit mode.
@@ -1242,7 +1243,7 @@ get_scno(struct tcb *tcp)
 # ifndef __X32_SYSCALL_BIT
 #  define __X32_SYSCALL_BIT	0x40000000
 # endif
-	int currpers;
+	unsigned int currpers;
 # if 1
 	/* GETREGSET of NT_PRSTATUS tells us regset size,
 	 * which unambiguously detects i386.
@@ -1530,7 +1531,7 @@ get_scno(struct tcb *tcp)
 	if (upeek(tcp->pid, 4*PT_R9, &scno) < 0)
 		return -1;
 #elif defined(TILE)
-	int currpers;
+	unsigned int currpers;
 	scno = tile_regs.regs[10];
 # ifdef __tilepro__
 	currpers = 1;
@@ -2660,7 +2661,7 @@ trace_syscall_exiting(struct tcb *tcp)
 		default:
 			if (u_error < 0)
 				tprintf("= -1 E??? (errno %ld)", u_error);
-			else if (u_error < nerrnos)
+			else if ((unsigned long) u_error < nerrnos)
 				tprintf("= -1 %s (%s)", errnoent[u_error],
 					strerror(u_error));
 			else
diff --git a/system.c b/system.c
index 435e2c18..86cb0243 100644
--- a/system.c
+++ b/system.c
@@ -433,7 +433,7 @@ sys_sysctl(struct tcb *tcp)
 		return printargs(tcp);
 
 	size = sizeof(int) * (unsigned long) info.nlen;
-	name = (size / sizeof(int) != info.nlen) ? NULL : malloc(size);
+	name = (size / sizeof(int) != (unsigned long) info.nlen) ? NULL : malloc(size);
 	if (name == NULL ||
 	    umoven(tcp, (unsigned long) info.name, size, (char *) name) < 0) {
 		free(name);
@@ -445,7 +445,7 @@ sys_sysctl(struct tcb *tcp)
 	}
 
 	if (entering(tcp)) {
-		int cnt = 0, max_cnt;
+		unsigned int cnt = 0, max_cnt;
 
 		tprints("{{");
 
@@ -540,7 +540,7 @@ sys_sysctl(struct tcb *tcp)
 			max_cnt = max_strlen;
 		while (cnt < max_cnt)
 			tprintf(", %x", name[cnt++]);
-		if (cnt < info.nlen)
+		if (cnt < (unsigned) info.nlen)
 			tprints(", ...");
 		tprintf("}, %d, ", info.nlen);
 	} else {
diff --git a/util.c b/util.c
index c78e962c..c8dc5914 100644
--- a/util.c
+++ b/util.c
@@ -141,7 +141,7 @@ tv_mul(struct timeval *tv, const struct timeval *a, int n)
 }
 
 const char *
-xlookup(const struct xlat *xlat, int val)
+xlookup(const struct xlat *xlat, const unsigned int val)
 {
 	for (; xlat->str != NULL; xlat++)
 		if (xlat->val == val)
@@ -210,7 +210,7 @@ next_set_bit(const void *bit_array, unsigned cur_bit, unsigned size_bits)
  * Print entry in struct xlat table, if there.
  */
 void
-printxval(const struct xlat *xlat, int val, const char *dflt)
+printxval(const struct xlat *xlat, const unsigned int val, const char *dflt)
 {
 	const char *str = xlookup(xlat, val);
 
@@ -414,7 +414,7 @@ printfd(struct tcb *tcp, int fd)
 void
 printuid(const char *text, unsigned long uid)
 {
-	tprintf((uid == -1) ? "%s%ld" : "%s%lu", text, uid);
+	tprintf(((long) uid == -1) ? "%s%ld" : "%s%lu", text, uid);
 }
 
 /*
@@ -564,7 +564,7 @@ string_quote(const char *instr, char *outstr, long len, int size)
  * If path length exceeds `n', append `...' to the output.
  */
 void
-printpathn(struct tcb *tcp, long addr, int n)
+printpathn(struct tcb *tcp, long addr, unsigned int n)
 {
 	char path[MAXPATHLEN + 1];
 	int nul_seen;
@@ -612,7 +612,7 @@ printstr(struct tcb *tcp, long addr, long len)
 {
 	static char *str = NULL;
 	static char *outstr;
-	int size;
+	unsigned int size;
 	int ellipsis;
 
 	if (!addr) {
@@ -658,7 +658,7 @@ printstr(struct tcb *tcp, long addr, long len)
 	 * or we were requested to print more than -s NUM chars)...
 	 */
 	ellipsis = (string_quote(str, outstr, len, size) &&
-			(len < 0 || len > max_strlen));
+			(len < 0 || (unsigned long) len > max_strlen));
 
 	tprints(outstr);
 	if (ellipsis)
@@ -1480,7 +1480,7 @@ setbpt(struct tcb *tcp)
 	 * godforsaken tables.
 	 */
 	if (clone_scno[current_personality] == 0) {
-		int i;
+		unsigned int i;
 		for (i = 0; i < nsyscalls; ++i)
 			if (sysent[i].sys_func == sys_clone) {
 				clone_scno[current_personality] = i;
-- 
2.40.0