diff --git a/src/Symfony/Bridge/Doctrine/Tests/Validator/DoctrineLoaderTest.php b/src/Symfony/Bridge/Doctrine/Tests/Validator/DoctrineLoaderTest.php
index 2dcab2533d..fbae0fbde2 100644
--- a/src/Symfony/Bridge/Doctrine/Tests/Validator/DoctrineLoaderTest.php
+++ b/src/Symfony/Bridge/Doctrine/Tests/Validator/DoctrineLoaderTest.php
@@ -173,7 +173,7 @@ class DoctrineLoaderTest extends TestCase
     public function regexpProvider()
     {
         return [
-            [false, null],
+            [true, null],
             [true, '{^'.preg_quote(DoctrineLoaderEntity::class).'$|^'.preg_quote(Entity::class).'$}'],
             [false, '{^'.preg_quote(Entity::class).'$}'],
         ];
diff --git a/src/Symfony/Bridge/Doctrine/Validator/DoctrineLoader.php b/src/Symfony/Bridge/Doctrine/Validator/DoctrineLoader.php
index 76a2b4d8b0..138b5d1cbb 100644
--- a/src/Symfony/Bridge/Doctrine/Validator/DoctrineLoader.php
+++ b/src/Symfony/Bridge/Doctrine/Validator/DoctrineLoader.php
@@ -43,7 +43,7 @@ final class DoctrineLoader implements LoaderInterface
     public function loadClassMetadata(ClassMetadata $metadata): bool
     {
         $className = $metadata->getClassName();
-        if (null === $this->classValidatorRegexp || !preg_match($this->classValidatorRegexp, $className)) {
+        if (null !== $this->classValidatorRegexp && !preg_match($this->classValidatorRegexp, $className)) {
             return false;
         }
 
diff --git a/src/Symfony/Component/Validator/DependencyInjection/AddAutoMappingConfigurationPass.php b/src/Symfony/Component/Validator/DependencyInjection/AddAutoMappingConfigurationPass.php
index 177f42e655..f28b78650c 100644
--- a/src/Symfony/Component/Validator/DependencyInjection/AddAutoMappingConfigurationPass.php
+++ b/src/Symfony/Component/Validator/DependencyInjection/AddAutoMappingConfigurationPass.php
@@ -59,6 +59,10 @@ class AddAutoMappingConfigurationPass implements CompilerPassInterface
         $validatorBuilder = $container->getDefinition($this->validatorBuilderService);
         foreach ($container->findTaggedServiceIds($this->tag) as $id => $tags) {
             $regexp = $this->getRegexp(array_merge($globalNamespaces, $servicesToNamespaces[$id] ?? []));
+            if (null === $regexp) {
+                $container->removeDefinition($id);
+                continue;
+            }
 
             $container->getDefinition($id)->setArgument('$classValidatorRegexp', $regexp);
             $validatorBuilder->addMethodCall('addLoader', [new Reference($id)]);
diff --git a/src/Symfony/Component/Validator/Tests/DependencyInjection/AddAutoMappingConfigurationPassTest.php b/src/Symfony/Component/Validator/Tests/DependencyInjection/AddAutoMappingConfigurationPassTest.php
index bce1101ef5..711bf8fc4f 100644
--- a/src/Symfony/Component/Validator/Tests/DependencyInjection/AddAutoMappingConfigurationPassTest.php
+++ b/src/Symfony/Component/Validator/Tests/DependencyInjection/AddAutoMappingConfigurationPassTest.php
@@ -81,6 +81,6 @@ class AddAutoMappingConfigurationPassTest extends TestCase
 
         (new AddAutoMappingConfigurationPass())->process($container);
 
-        $this->assertNull($container->getDefinition('loader')->getArgument('$classValidatorRegexp'));
+        $this->assertFalse($container->hasDefinition('loader'));
     }
 }