diff --git a/NEWS b/NEWS
index 0c80ffefb1b2..5779a0a0a545 100644
--- a/NEWS
+++ b/NEWS
@@ -27,6 +27,10 @@ PHP                                                                        NEWS
     so an in-process engine restart keeps growing the map_ptr table).
     (David Carlier)
 
+- Curl:
+  . Fixed curl_setopt() ignoring errors while building multipart POST fields.
+    (Ilia Alshanetsky)
+
 - Date:
   . Fixed bug GH-20503 (Assertion failure with ext/date DateInterval property
     hash construction). (heathdutton)
diff --git a/ext/curl/interface.c b/ext/curl/interface.c
index 8f82bd7f285d..5f811d090c95 100644
--- a/ext/curl/interface.c
+++ b/ext/curl/interface.c
@@ -1574,14 +1574,18 @@ static inline zend_result build_mime_structure_from_hash(php_curl *ch, zval *zpo
 			zval *current_element;
 
 			ZEND_HASH_FOREACH_VAL(HASH_OF(current), current_element) {
-				add_simple_field(mime, string_key, current_element);
+				if ((form_error = add_simple_field(mime, string_key, current_element)) != CURLE_OK && error == CURLE_OK) {
+					error = form_error;
+				}
 			} ZEND_HASH_FOREACH_END();
 
 			zend_string_release_ex(string_key, 0);
 			continue;
 		}
 
-		add_simple_field(mime, string_key, current);
+		if ((form_error = add_simple_field(mime, string_key, current)) != CURLE_OK && error == CURLE_OK) {
+			error = form_error;
+		}
 
 		zend_string_release_ex(string_key, 0);
 	} ZEND_HASH_FOREACH_END();