diff --git a/jerry-core/config.h b/jerry-core/config.h
index 784ddd16c..4d0960747 100644
--- a/jerry-core/config.h
+++ b/jerry-core/config.h
@@ -86,6 +86,10 @@
            && CONFIG_ECMA_NUMBER_TYPE != CONFIG_ECMA_NUMBER_FLOAT64 */
 #endif /* !CONFIG_ECMA_NUMBER_TYPE */
 
+#if (!defined (CONFIG_DISABLE_DATE_BUILTIN) && (CONFIG_ECMA_NUMBER_TYPE == CONFIG_ECMA_NUMBER_FLOAT32))
+#  error "Date does not support float32"
+#endif
+
 /**
  * Representation for ecma-characters
  */
diff --git a/jerry-core/ecma/builtin-objects/ecma-builtin-string-prototype.c b/jerry-core/ecma/builtin-objects/ecma-builtin-string-prototype.c
index 2144de5dd..b35a17135 100644
--- a/jerry-core/ecma/builtin-objects/ecma-builtin-string-prototype.c
+++ b/jerry-core/ecma/builtin-objects/ecma-builtin-string-prototype.c
@@ -817,7 +817,7 @@ ecma_builtin_string_prototype_object_replace_get_string (ecma_builtin_replace_se
 
     if (ecma_is_value_empty (ret_value))
     {
-      arguments_list[match_length] = ecma_make_number_value (context_p->match_start);
+      arguments_list[match_length] = ecma_make_uint32_value (context_p->match_start);
       arguments_list[match_length + 1] = ecma_copy_value (context_p->input_string);
 
       ECMA_TRY_CATCH (result_value,
@@ -1117,7 +1117,7 @@ ecma_builtin_string_prototype_object_replace_loop (ecma_builtin_replace_search_c
           ECMA_TRY_CATCH (put_value,
                           ecma_op_object_put (regexp_obj_p,
                                               last_index_string_p,
-                                              ecma_make_number_value (context_p->match_end + 1),
+                                              ecma_make_uint32_value (context_p->match_end + 1),
                                               true),
                           ret_value);
 
@@ -1529,7 +1529,7 @@ ecma_builtin_helper_split_match (ecma_value_t input_string, /**< first argument
       ecma_property_value_t *index_prop_value_p = ecma_get_named_data_property (obj_p, magic_index_str_p);
 
       ecma_number_t index_num = ecma_get_number_from_value (index_prop_value_p->value);
-      ecma_value_assign_number (&index_prop_value_p->value, index_num + start_idx);
+      ecma_value_assign_number (&index_prop_value_p->value, index_num + (ecma_number_t) start_idx);
 
       ecma_deref_ecma_string (magic_index_str_p);
     }
diff --git a/jerry-core/ecma/operations/ecma-regexp-object.c b/jerry-core/ecma/operations/ecma-regexp-object.c
index faa514e41..56ce38b19 100644
--- a/jerry-core/ecma/operations/ecma-regexp-object.c
+++ b/jerry-core/ecma/operations/ecma-regexp-object.c
@@ -1375,8 +1375,8 @@ ecma_regexp_exec_helper (ecma_value_t regexp_value, /**< RegExp object */
     if (sub_str_p != NULL
         && input_buffer_p != NULL)
     {
-      lastindex_num = lit_utf8_string_length (input_buffer_p,
-                                              (lit_utf8_size_t) (sub_str_p - input_buffer_p));
+      lastindex_num = (ecma_number_t) lit_utf8_string_length (input_buffer_p,
+                                                              (lit_utf8_size_t) (sub_str_p - input_buffer_p));
     }
     else
     {
diff --git a/tests/jerry/array-prototype-lastindexof.js b/tests/jerry/array-prototype-lastindexof.js
index c158eeb73..4aa2c5f4f 100644
--- a/tests/jerry/array-prototype-lastindexof.js
+++ b/tests/jerry/array-prototype-lastindexof.js
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// This test will not pass on FLOAT32 due to precision issues
+
 var obj = {};
 var array = ["foo", 19, "bar", obj, "foo", 29, "baz"];
 
diff --git a/tests/jerry/array-prototype-push.js b/tests/jerry/array-prototype-push.js
index 717843743..84a55e9bf 100644
--- a/tests/jerry/array-prototype-push.js
+++ b/tests/jerry/array-prototype-push.js
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// This test will not pass on FLOAT32 due to precision issues
+
 var len;
 var d = [];
 assert (d.length === 0);
diff --git a/tests/jerry/array-prototype-reduce-right.js b/tests/jerry/array-prototype-reduce-right.js
index 1e5a1f81b..a9a71cb27 100644
--- a/tests/jerry/array-prototype-reduce-right.js
+++ b/tests/jerry/array-prototype-reduce-right.js
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// This test will not pass on FLOAT32 due to precision issues
+
 var func = function(a, b) {
   return a + b;
 }
diff --git a/tests/jerry/array-prototype-reduce.js b/tests/jerry/array-prototype-reduce.js
index 5b787bb85..6193ec7f0 100644
--- a/tests/jerry/array-prototype-reduce.js
+++ b/tests/jerry/array-prototype-reduce.js
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// This test will not pass on FLOAT32 due to precision issues
+
 var func = function(a, b) {
   return a + b;
 }
diff --git a/tests/jerry/array-prototype-slice.js b/tests/jerry/array-prototype-slice.js
index 7a9b9a67d..bb1a2e800 100644
--- a/tests/jerry/array-prototype-slice.js
+++ b/tests/jerry/array-prototype-slice.js
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// This test will not pass on FLOAT32 due to precision issues
+
 var array = [54, undefined, "Lemon", -127];
 
 var array1 = array.slice();
diff --git a/tests/jerry/array-prototype-splice.js b/tests/jerry/array-prototype-splice.js
index d3249af86..c5c01ab50 100644
--- a/tests/jerry/array-prototype-splice.js
+++ b/tests/jerry/array-prototype-splice.js
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// This test will not pass on FLOAT32 due to precision issues
+
 function setDefaultValues()
 {
   return [54, undefined, -127, "sunshine"];
diff --git a/tests/jerry/global-uri-coding.js b/tests/jerry/global-uri-coding.js
index 28de4ba1d..169507bd4 100644
--- a/tests/jerry/global-uri-coding.js
+++ b/tests/jerry/global-uri-coding.js
@@ -14,6 +14,8 @@
 
 // URI encoding
 
+// This test will not pass on FLOAT32 due to precision issues
+
 function checkEncodeURIParseError (str)
 {
   try {
diff --git a/tests/jerry/json-parse.js b/tests/jerry/json-parse.js
index 91f75a2ea..6b4986d6f 100644
--- a/tests/jerry/json-parse.js
+++ b/tests/jerry/json-parse.js
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// This test will not pass on FLOAT32 due to precision issues
+
 // Checking primitve types
 var str;
 var result;
diff --git a/tests/jerry/number-prototype-to-string.js b/tests/jerry/number-prototype-to-string.js
index 8322480a0..f40be51fc 100644
--- a/tests/jerry/number-prototype-to-string.js
+++ b/tests/jerry/number-prototype-to-string.js
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// This test will not pass on FLOAT32 due to precision issues
+
 assert((NaN).toString() === "NaN");
 assert((-Infinity).toString() === "-Infinity");
 assert((Infinity).toString() === "Infinity");