diff --git a/jerry-core/ecma/builtin-objects/ecma-builtin-helpers-date.cpp b/jerry-core/ecma/builtin-objects/ecma-builtin-helpers-date.cpp
index 74c0c7b58..d19d059c4 100644
--- a/jerry-core/ecma/builtin-objects/ecma-builtin-helpers-date.cpp
+++ b/jerry-core/ecma/builtin-objects/ecma-builtin-helpers-date.cpp
@@ -1062,7 +1062,7 @@ ecma_date_value_to_string (ecma_number_t datetime_number) /**< datetime */
   /*
    * Character length of the result string.
    */
-  constexpr uint32_t result_string_length = 33;
+  const uint32_t result_string_length = 33;
 
   lit_utf8_byte_t character_buffer[result_string_length];
   lit_utf8_byte_t *dest_p = character_buffer;
@@ -1110,7 +1110,7 @@ ecma_date_value_to_utc_string (ecma_number_t datetime_number) /**< datetime */
   /*
    * Character length of the result string.
    */
-  constexpr uint32_t result_string_length = 29;
+  const uint32_t result_string_length = 29;
 
   lit_utf8_byte_t character_buffer[result_string_length];
   lit_utf8_byte_t *dest_p = character_buffer;
@@ -1151,7 +1151,7 @@ ecma_date_value_to_iso_string (ecma_number_t datetime_number) /**<datetime */
   /*
    * Character length of the result string.
    */
-  constexpr uint32_t result_string_length = 24;
+  const uint32_t result_string_length = 24;
 
   lit_utf8_byte_t character_buffer[result_string_length];
   lit_utf8_byte_t *dest_p = character_buffer;
@@ -1212,7 +1212,7 @@ ecma_date_value_to_date_string (ecma_number_t datetime_number) /**<datetime */
   /*
    * Character length of the result string.
    */
-  constexpr uint32_t result_string_length = 10;
+  const uint32_t result_string_length = 10;
 
   lit_utf8_byte_t character_buffer[result_string_length];
   lit_utf8_byte_t *dest_p = character_buffer;
@@ -1256,7 +1256,7 @@ ecma_date_value_to_time_string (ecma_number_t datetime_number) /**<datetime */
   /*
    * Character length of the result string.
    */
-  constexpr uint32_t result_string_length = 12;
+  const uint32_t result_string_length = 12;
 
   lit_utf8_byte_t character_buffer[result_string_length];
   lit_utf8_byte_t *dest_p = character_buffer;