diff --git a/lib/util/event.c b/lib/util/event.c
index d2a6c8c6a..41927702d 100644
--- a/lib/util/event.c
+++ b/lib/util/event.c
@@ -826,10 +826,9 @@ sudo_ev_get_timeleft_v2(struct sudo_event *ev, struct timespec *ts)
 {
     debug_decl(sudo_ev_get_timeleft, SUDO_DEBUG_EVENT);
 
-    if (sudo_ev_pending_v1(ev, SUDO_EV_TIMEOUT, ts) != SUDO_EV_TIMEOUT) {
-	sudo_timespecclear(ts);
+    sudo_timespecclear(ts);
+    if (sudo_ev_pending_v1(ev, SUDO_EV_TIMEOUT, ts) != SUDO_EV_TIMEOUT)
 	debug_return_int(-1);
-    }
     debug_return_int(0);
 }
 
@@ -846,6 +845,7 @@ sudo_ev_pending_v1(struct sudo_event *ev, short events, struct timespec *ts)
 	debug_return_int(0);
 
     ret = ev->events & events;
+    CLR(ret, SUDO_EV_TIMEOUT);
     if (ISSET(ev->flags, SUDO_EVQ_TIMEOUTS) && ISSET(events, SUDO_EV_TIMEOUT)) {
 	ret |= SUDO_EV_TIMEOUT;
 	if (ts != NULL) {
diff --git a/plugins/sudoers/cvtsudoers_pwutil.c b/plugins/sudoers/cvtsudoers_pwutil.c
index 47c487679..a7b163e91 100644
--- a/plugins/sudoers/cvtsudoers_pwutil.c
+++ b/plugins/sudoers/cvtsudoers_pwutil.c
@@ -58,6 +58,8 @@ do {							\
 	if ((src)->name) {				\
 		size = strlen((src)->name) + 1;		\
 		total += size;				\
+	} else {                                        \
+		size = 0;				\
 	}                                               \
 } while (0)
 
@@ -65,7 +67,7 @@ do {							\
 do {							\
 	if ((src)->name) {				\
 		memcpy(cp, (src)->name, size);		\
-		(dst)->name = cp;				\
+		(dst)->name = cp;			\
 		cp += size;				\
 	}						\
 } while (0)
@@ -81,7 +83,10 @@ struct cache_item *
 cvtsudoers_make_pwitem(uid_t uid, const char *name)
 {
     char *cp, uidstr[MAX_UID_T_LEN + 2];
-    size_t nsize, psize, csize, gsize, dsize, ssize, total;
+    size_t nsize, psize, gsize, dsize, ssize, total;
+#ifdef HAVE_LOGIN_CAP_H
+    size_t csize;
+#endif
     struct cache_item_pw *pwitem;
     struct passwd pw, *newpw;
     struct sudoers_string *s = NULL;
@@ -128,7 +133,6 @@ cvtsudoers_make_pwitem(uid_t uid, const char *name)
     pw.pw_dir = "/";
 
     /* Allocate in one big chunk for easy freeing. */
-    nsize = psize = csize = gsize = dsize = ssize = 0;
     total = sizeof(*pwitem);
     FIELD_SIZE(&pw, pw_name, nsize);
     FIELD_SIZE(&pw, pw_passwd, psize);
@@ -188,7 +192,7 @@ struct cache_item *
 cvtsudoers_make_gritem(gid_t gid, const char *name)
 {
     char *cp, gidstr[MAX_UID_T_LEN + 2];
-    size_t nsize, psize, nmem, total, len;
+    size_t nsize, psize, total, len, nmem = 0;
     struct cache_item_gr *gritem;
     struct group gr, *newgr;
     struct sudoers_string *s = NULL;
@@ -231,7 +235,6 @@ cvtsudoers_make_gritem(gid_t gid, const char *name)
     gr.gr_gid = gid;
 
     /* Allocate in one big chunk for easy freeing. */
-    nsize = psize = nmem = 0;
     total = sizeof(*gritem);
     FIELD_SIZE(&gr, gr_name, nsize);
     FIELD_SIZE(&gr, gr_passwd, psize);
diff --git a/plugins/sudoers/defaults.c b/plugins/sudoers/defaults.c
index 2c477e814..a72b3de22 100644
--- a/plugins/sudoers/defaults.c
+++ b/plugins/sudoers/defaults.c
@@ -199,7 +199,7 @@ find_default(const char *name, const char *file, int lineno, bool quiet)
  */
 static bool
 parse_default_entry(struct sudo_defs_types *def, const char *val, int op,
-    union sudo_defs_val *sd_un, const char *file, int lineno, bool quiet)
+    const char *file, int lineno, bool quiet)
 {
     int rc;
     debug_decl(parse_default_entry, SUDOERS_DEBUG_DEFAULTS);
@@ -243,10 +243,10 @@ parse_default_entry(struct sudo_defs_types *def, const char *val, int op,
 
     switch (def->type & T_MASK) {
 	case T_LOGFAC:
-	    rc = store_syslogfac(val, sd_un);
+	    rc = store_syslogfac(val, &def->sd_un);
 	    break;
 	case T_LOGPRI:
-	    rc = store_syslogpri(val, sd_un);
+	    rc = store_syslogpri(val, &def->sd_un);
 	    break;
 	case T_STR:
 	    if (ISSET(def->type, T_PATH) && val != NULL && *val != '/') {
@@ -262,16 +262,16 @@ parse_default_entry(struct sudo_defs_types *def, const char *val, int op,
 		rc = -1;
 		break;
 	    }
-	    rc =  store_str(val, sd_un);
+	    rc =  store_str(val, &def->sd_un);
 	    break;
 	case T_INT:
-	    rc = store_int(val, sd_un);
+	    rc = store_int(val, &def->sd_un);
 	    break;
 	case T_UINT:
-	    rc = store_uint(val, sd_un);
+	    rc = store_uint(val, &def->sd_un);
 	    break;
 	case T_MODE:
-	    rc = store_mode(val, sd_un);
+	    rc = store_mode(val, &def->sd_un);
 	    break;
 	case T_FLAG:
 	    if (val != NULL) {
@@ -287,20 +287,20 @@ parse_default_entry(struct sudo_defs_types *def, const char *val, int op,
 		rc = -1;
 		break;
 	    }
-	    sd_un->flag = op;
+	    def->sd_un.flag = op;
 	    rc = true;
 	    break;
 	case T_LIST:
-	    rc = store_list(val, sd_un, op);
+	    rc = store_list(val, &def->sd_un, op);
 	    break;
 	case T_TIMEOUT:
-	    rc = store_timeout(val, sd_un);
+	    rc = store_timeout(val, &def->sd_un);
 	    break;
 	case T_TUPLE:
-	    rc = store_tuple(val, sd_un, def->values);
+	    rc = store_tuple(val, &def->sd_un, def->values);
 	    break;
 	case T_TIMESPEC:
-	    rc = store_timespec(val, sd_un);
+	    rc = store_timespec(val, &def->sd_un);
 	    break;
 	default:
 	    if (!quiet) {
@@ -371,7 +371,7 @@ set_default(const char *var, const char *val, int op, const char *file,
     if (idx != -1) {
 	/* Set parsed value in sudo_defs_table and run callback (if any). */
 	struct sudo_defs_types *def = &sudo_defs_table[idx];
-	if (parse_default_entry(def, val, op, &def->sd_un, file, lineno, quiet))
+	if (parse_default_entry(def, val, op, file, lineno, quiet))
 	    debug_return_bool(run_callback(def));
     }
     debug_return_bool(false);
@@ -392,7 +392,7 @@ set_early_default(const char *var, const char *val, int op, const char *file,
     if (idx != -1) {
 	/* Set parsed value in sudo_defs_table but defer callback (if any). */
 	struct sudo_defs_types *def = &sudo_defs_table[idx];
-	if (parse_default_entry(def, val, op, &def->sd_un, file, lineno, quiet)) {
+	if (parse_default_entry(def, val, op, file, lineno, quiet)) {
 	    early->run_callback = true;
 	    debug_return_bool(true);
 	}
@@ -776,12 +776,11 @@ check_defaults(struct sudoers_parse_tree *parse_tree, bool quiet)
     TAILQ_FOREACH(d, &parse_tree->defaults, entries) {
 	idx = find_default(d->var, d->file, d->lineno, quiet);
 	if (idx != -1) {
-	    struct sudo_defs_types *def = &sudo_defs_table[idx];
-	    union sudo_defs_val sd_un;
-	    memset(&sd_un, 0, sizeof(sd_un));
-	    if (parse_default_entry(def, d->val, d->op, &sd_un, d->file,
+	    struct sudo_defs_types def = sudo_defs_table[idx];
+	    memset(&def.sd_un, 0, sizeof(def.sd_un));
+	    if (parse_default_entry(&def, d->val, d->op, d->file,
 		d->lineno, quiet)) {
-		free_defs_val(def->type, &sd_un);
+		free_defs_val(def.type, &def.sd_un);
 		continue;
 	    }
 	}
diff --git a/plugins/sudoers/linux_audit.c b/plugins/sudoers/linux_audit.c
index 3fe1ff0c6..89e5e1021 100644
--- a/plugins/sudoers/linux_audit.c
+++ b/plugins/sudoers/linux_audit.c
@@ -66,7 +66,7 @@ int
 linux_audit_command(char *const argv[], int result)
 {
     int au_fd, rc = -1;
-    char *command, *cp;
+    char *cp, *command = NULL;
     char * const *av;
     size_t size, n;
     debug_decl(linux_audit_command, SUDOERS_DEBUG_AUDIT);
@@ -78,7 +78,8 @@ linux_audit_command(char *const argv[], int result)
     /* Convert argv to a flat string. */
     for (size = 0, av = argv; *av != NULL; av++)
 	size += strlen(*av) + 1;
-    command = malloc(size);
+    if (size != 0)
+	command = malloc(size);
     if (command == NULL) {
 	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));
 	goto done;
diff --git a/plugins/sudoers/logging.c b/plugins/sudoers/logging.c
index 88e3cd3d2..81da0f788 100644
--- a/plugins/sudoers/logging.c
+++ b/plugins/sudoers/logging.c
@@ -786,7 +786,7 @@ send_mail(const char *fmt, ...)
 	    break;
 	case 0:
 	    /* Child. */
-	    switch (pid = fork()) {
+	    switch (fork()) {
 		case -1:
 		    /* Error. */
 		    mysyslog(LOG_ERR, _("unable to fork: %m"));
diff --git a/plugins/sudoers/pwutil.c b/plugins/sudoers/pwutil.c
index 19d8005d0..720939602 100644
--- a/plugins/sudoers/pwutil.c
+++ b/plugins/sudoers/pwutil.c
@@ -856,7 +856,6 @@ int
 sudo_set_grlist(struct passwd *pw, char * const *groups)
 {
     struct cache_item key, *item;
-    struct rbnode *node;
     debug_decl(sudo_set_grlist, SUDOERS_DEBUG_NSS);
 
     if (grlist_cache == NULL) {
@@ -872,7 +871,7 @@ sudo_set_grlist(struct passwd *pw, char * const *groups)
      */
     key.k.name = pw->pw_name;
     getauthregistry(NULL, key.registry);
-    if ((node = rbfind(grlist_cache, &key)) == NULL) {
+    if (rbfind(grlist_cache, &key) == NULL) {
 	if ((item = make_grlist_item(pw, groups)) == NULL) {
 	    sudo_warnx(U_("unable to parse groups for %s"), pw->pw_name);
 	    debug_return_int(-1);
@@ -958,7 +957,6 @@ int
 sudo_set_gidlist(struct passwd *pw, char * const *gids, unsigned int type)
 {
     struct cache_item key, *item;
-    struct rbnode *node;
     debug_decl(sudo_set_gidlist, SUDOERS_DEBUG_NSS);
 
     if (gidlist_cache == NULL) {
@@ -975,7 +973,7 @@ sudo_set_gidlist(struct passwd *pw, char * const *gids, unsigned int type)
     key.k.name = pw->pw_name;
     key.type = type;
     getauthregistry(NULL, key.registry);
-    if ((node = rbfind(gidlist_cache, &key)) == NULL) {
+    if (rbfind(gidlist_cache, &key) == NULL) {
 	if ((item = make_gidlist_item(pw, gids, type)) == NULL) {
 	    sudo_warnx(U_("unable to parse gids for %s"), pw->pw_name);
 	    debug_return_int(-1);
diff --git a/plugins/sudoers/pwutil_impl.c b/plugins/sudoers/pwutil_impl.c
index 363fd16b4..2e39e0802 100644
--- a/plugins/sudoers/pwutil_impl.c
+++ b/plugins/sudoers/pwutil_impl.c
@@ -54,6 +54,8 @@ do {							\
 	if (src->name) {				\
 		size = strlen(src->name) + 1;		\
 		total += size;				\
+	} else {                                        \
+		size = 0;				\
 	}                                               \
 } while (0)
 
@@ -78,7 +80,10 @@ sudo_make_pwitem(uid_t uid, const char *name)
 {
     char *cp;
     const char *pw_shell;
-    size_t nsize, psize, csize, gsize, dsize, ssize, total;
+    size_t nsize, psize, gsize, dsize, ssize, total;
+#ifdef HAVE_LOGIN_CAP_H
+    size_t csize;
+#endif
     struct cache_item_pw *pwitem;
     struct passwd *pw, *newpw;
     debug_decl(sudo_make_pwitem, SUDOERS_DEBUG_NSS);
@@ -95,7 +100,6 @@ sudo_make_pwitem(uid_t uid, const char *name)
 	? _PATH_BSHELL : pw->pw_shell;
 
     /* Allocate in one big chunk for easy freeing. */
-    nsize = psize = csize = gsize = dsize = ssize = 0;
     total = sizeof(*pwitem);
     FIELD_SIZE(pw, pw_name, nsize);
     FIELD_SIZE(pw, pw_passwd, psize);
@@ -160,7 +164,7 @@ struct cache_item *
 sudo_make_gritem(gid_t gid, const char *name)
 {
     char *cp;
-    size_t nsize, psize, nmem, total, len;
+    size_t nsize, psize, total, len, nmem = 0;
     struct cache_item_gr *gritem;
     struct group *gr, *newgr;
     debug_decl(sudo_make_gritem, SUDOERS_DEBUG_NSS);
@@ -173,7 +177,6 @@ sudo_make_gritem(gid_t gid, const char *name)
     }
 
     /* Allocate in one big chunk for easy freeing. */
-    nsize = psize = nmem = 0;
     total = sizeof(*gritem);
     FIELD_SIZE(gr, gr_name, nsize);
     FIELD_SIZE(gr, gr_passwd, psize);
diff --git a/src/selinux.c b/src/selinux.c
index 4a0f4524c..5f74c81cc 100644
--- a/src/selinux.c
+++ b/src/selinux.c
@@ -480,6 +480,10 @@ selinux_execve(int fd, const char *path, char *const argv[], char *envp[],
      */
     for (argc = 0; argv[argc] != NULL; argc++)
 	continue;
+    if (argc == 0) {
+	errno = EINVAL;
+	debug_return;
+    }
     nargv = reallocarray(NULL, argc + 3, sizeof(char *));
     if (nargv == NULL) {
 	sudo_warnx(U_("%s: %s"), __func__, U_("unable to allocate memory"));