diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer.php
index 51d42494d1def..bae85a86fbec5 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer.php
@@ -121,7 +121,7 @@ public function reverseTransform($value)
         $outputTz = new \DateTimeZone($this->outputTimezone);
         $dateTime = \DateTime::createFromFormat($this->parseFormat, $value, $outputTz);
 
-        $lastErrors = \DateTime::getLastErrors();
+        $lastErrors = \DateTime::getLastErrors() ?: ['error_count' => 0, 'warning_count' => 0];
 
         if (0 < $lastErrors['warning_count'] || 0 < $lastErrors['error_count']) {
             throw new TransformationFailedException(implode(', ', array_merge(array_values($lastErrors['warnings']), array_values($lastErrors['errors']))));
diff --git a/src/Symfony/Component/Validator/Constraints/DateTimeValidator.php b/src/Symfony/Component/Validator/Constraints/DateTimeValidator.php
index 1a3ae3784b422..5f2c7a8ef140e 100644
--- a/src/Symfony/Component/Validator/Constraints/DateTimeValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/DateTimeValidator.php
@@ -48,7 +48,7 @@ public function validate($value, Constraint $constraint)
 
         \DateTime::createFromFormat($constraint->format, $value);
 
-        $errors = \DateTime::getLastErrors();
+        $errors = \DateTime::getLastErrors() ?: ['error_count' => 0, 'warnings' => []];
 
         if (0 < $errors['error_count']) {
             $this->context->buildViolation($constraint->message)