diff --git a/plugins/check_dns.c b/plugins/check_dns.c
index 5e20214c..468bc958 100644
--- a/plugins/check_dns.c
+++ b/plugins/check_dns.c
@@ -87,7 +87,6 @@ main (int argc, char **argv)
   struct timeval tv;
   bool parse_address = false; /* This flag scans for Address: but only after Name: */
   output chld_out, chld_err;
-  size_t i;
   bool is_nxdomain = false;
 
   setlocale (LC_ALL, "");
diff --git a/plugins/check_ntp_peer.c b/plugins/check_ntp_peer.c
index 4fb9018c..464a9e10 100644
--- a/plugins/check_ntp_peer.c
+++ b/plugins/check_ntp_peer.c
@@ -558,7 +558,6 @@ char *perfd_truechimers (int num_truechimers)
 
 int main(int argc, char *argv[]){
 	int result, offset_result, stratum, num_truechimers;
-	int oresult, jresult, sresult, tresult = STATE_UNKNOWN;
 	double offset=0, jitter=0;
 	char *result_line, *perfdata_line;
 
@@ -595,18 +594,28 @@ int main(int argc, char *argv[]){
 			result = STATE_UNKNOWN;
 		result = max_state_alt(result, get_status(fabs(offset), offset_thresholds));
 	}
-	oresult = result;
+
+	int oresult = result;
+
+
+	int tresult = STATE_UNKNOWN;
 	
 	if(do_truechimers) {
 		tresult = get_status(num_truechimers, truechimer_thresholds);
 		result = max_state_alt(result, tresult);
 	}
 
+
+	int sresult = STATE_UNKNOWN;
+
 	if(do_stratum) {
 		sresult = get_status(stratum, stratum_thresholds);
 		result = max_state_alt(result, sresult);
 	}
 
+
+	int jresult = STATE_UNKNOWN;
+
 	if(do_jitter) {
 		jresult = get_status(jitter, jitter_thresholds);
 		result = max_state_alt(result, jresult);
diff --git a/plugins/utils.c b/plugins/utils.c
index e871c5f7..aff17906 100644
--- a/plugins/utils.c
+++ b/plugins/utils.c
@@ -258,16 +258,25 @@ bool is_int64(char *number, int64_t *target) {
  */
 bool is_uint64(char *number, uint64_t *target) {
 	errno = 0;
-	uint64_t tmp = strtoll(number, NULL, 10);
+	char *endptr = { 0 };
+	unsigned long long tmp = strtoull(number, &endptr, 10);
+
 	if (errno != 0) {
 		return false;
 	}
-	if (tmp < 0 || tmp > UINT64_MAX) {
+
+	if (*endptr != '\0') {
 		return false;
 	}
-	if (target != NULL) {
-		*target = tmp;
+
+	if (tmp > UINT64_MAX) {
+		return false;
 	}
+
+	if (target != NULL) {
+		*target = (uint64_t)tmp;
+	}
+
 	return true;
 }