diff --git a/kafka_consumer.c b/kafka_consumer.c
index d48abbd..2c0eddb 100644
--- a/kafka_consumer.c
+++ b/kafka_consumer.c
@@ -767,7 +767,7 @@ PHP_METHOD(RdKafka_KafkaConsumer, queryWatermarkOffsets)
     object_intern *intern;
     char *topic;
     size_t topic_length;
-    long low, high;
+    int64_t low, high;
     zend_long partition, timeout;
     zval *lowResult, *highResult;
     rd_kafka_resp_err_t err;
@@ -791,8 +791,8 @@ PHP_METHOD(RdKafka_KafkaConsumer, queryWatermarkOffsets)
         return;
     }
 
-    ZVAL_LONG(lowResult, low);
-    ZVAL_LONG(highResult, high);
+    ZVAL_LONG(lowResult, (zend_long) low);
+    ZVAL_LONG(highResult, (zend_long) high);
 }
 /* }}} */
 
diff --git a/rdkafka.c b/rdkafka.c
index 727fc8c..783de1b 100644
--- a/rdkafka.c
+++ b/rdkafka.c
@@ -721,7 +721,7 @@ PHP_METHOD(RdKafka, queryWatermarkOffsets)
     kafka_object *intern;
     char *topic;
     size_t topic_length;
-    long low, high;
+    int64_t low, high;
     zend_long partition, timeout;
     zval *lowResult, *highResult;
     rd_kafka_resp_err_t err;
@@ -745,8 +745,8 @@ PHP_METHOD(RdKafka, queryWatermarkOffsets)
         return;
     }
 
-    ZVAL_LONG(lowResult, low);
-    ZVAL_LONG(highResult, high);
+    ZVAL_LONG(lowResult, (zend_long) low);
+    ZVAL_LONG(highResult, (zend_long) high);
 }
 /* }}} */
 
diff --git a/tests/bug508.phpt b/tests/bug508.phpt
index c36d994..d4f24ff 100644
--- a/tests/bug508.phpt
+++ b/tests/bug508.phpt
@@ -73,7 +73,7 @@ array(10) {
   ["topic_name"]=>
   string(%d) "test_rdkafka_%s"
   ["timestamp"]=>
-  int(%d)
+  int(%f)
   ["partition"]=>
   int(0)
   ["payload"]=>
diff --git a/topic.c b/topic.c
index f1c0f7f..d3a9f6b 100644
--- a/topic.c
+++ b/topic.c
@@ -128,7 +128,7 @@ PHP_METHOD(RdKafka_ConsumerTopic, consumeCallback)
     }
 
     if (partition < 0 || partition > 0x7FFFFFFF) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
@@ -165,7 +165,7 @@ PHP_METHOD(RdKafka_ConsumerTopic, consumeQueueStart)
     }
 
     if (partition != RD_KAFKA_PARTITION_UA && (partition < 0 || partition > 0x7FFFFFFF)) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
@@ -223,7 +223,7 @@ PHP_METHOD(RdKafka_ConsumerTopic, consumeStart)
     }
 
     if (partition != RD_KAFKA_PARTITION_UA && (partition < 0 || partition > 0x7FFFFFFF)) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
@@ -275,7 +275,7 @@ PHP_METHOD(RdKafka_ConsumerTopic, consumeStop)
     }
 
     if (partition != RD_KAFKA_PARTITION_UA && (partition < 0 || partition > 0x7FFFFFFF)) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
@@ -316,7 +316,7 @@ PHP_METHOD(RdKafka_ConsumerTopic, consume)
     }
 
     if (partition != RD_KAFKA_PARTITION_UA && (partition < 0 || partition > 0x7FFFFFFF)) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
@@ -357,12 +357,12 @@ PHP_METHOD(RdKafka_ConsumerTopic, consumeBatch)
     }
 
     if (0 >= batch_size) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for batch_size", batch_size);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for batch_size", batch_size);
         return;
     }
 
     if (partition != RD_KAFKA_PARTITION_UA && (partition < 0 || partition > 0x7FFFFFFF)) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
@@ -406,7 +406,7 @@ PHP_METHOD(RdKafka_ConsumerTopic, offsetStore)
     }
 
     if (partition < 0 || partition > 0x7FFFFFFF) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
@@ -455,12 +455,12 @@ PHP_METHOD(RdKafka_ProducerTopic, produce)
     ZEND_PARSE_PARAMETERS_END();
 
     if (partition != RD_KAFKA_PARTITION_UA && (partition < 0 || partition > 0x7FFFFFFF)) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
     if (msgflags != 0 && msgflags != RD_KAFKA_MSG_F_BLOCK) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Invalid value '%ld' for $msgflags", msgflags);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Invalid value '" ZEND_LONG_FMT "' for $msgflags", msgflags);
         return;
     }
 
@@ -524,12 +524,12 @@ PHP_METHOD(RdKafka_ProducerTopic, producev)
     ZEND_PARSE_PARAMETERS_END();
 
     if (partition != RD_KAFKA_PARTITION_UA && (partition < 0 || partition > 0x7FFFFFFF)) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '%ld' for $partition", partition);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Out of range value '" ZEND_LONG_FMT "' for $partition", partition);
         return;
     }
 
     if (msgflags != 0 && msgflags != RD_KAFKA_MSG_F_BLOCK) {
-        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Invalid value '%ld' for $msgflags", msgflags);
+        zend_throw_exception_ex(spl_ce_InvalidArgumentException, 0, "Invalid value '" ZEND_LONG_FMT "' for $msgflags", msgflags);
         return;
     }