diff --git a/src/Symfony/Bridge/PhpUnit/bin/simple-phpunit.php b/src/Symfony/Bridge/PhpUnit/bin/simple-phpunit.php
index 247aff665f..697687b213 100644
--- a/src/Symfony/Bridge/PhpUnit/bin/simple-phpunit.php
+++ b/src/Symfony/Bridge/PhpUnit/bin/simple-phpunit.php
@@ -119,6 +119,8 @@ if (!file_exists("$PHPUNIT_DIR/phpunit-$PHPUNIT_VERSION/phpunit") || md5_file(__
     if (5.1 <= $PHPUNIT_VERSION && $PHPUNIT_VERSION < 5.4) {
         passthru("$COMPOSER require --no-update phpunit/phpunit-mock-objects \"~3.1.0\"");
     }
+
+    passthru("$COMPOSER config --unset platform");
     if (file_exists($path = $root.'/vendor/symfony/phpunit-bridge')) {
         passthru("$COMPOSER require --no-update symfony/phpunit-bridge \"*@dev\"");
         passthru("$COMPOSER config repositories.phpunit-bridge path ".escapeshellarg(str_replace('/', DIRECTORY_SEPARATOR, $path)));
diff --git a/src/Symfony/Component/Config/Definition/Builder/NodeDefinition.php b/src/Symfony/Component/Config/Definition/Builder/NodeDefinition.php
index a771a43cd2..f6d9e69266 100644
--- a/src/Symfony/Component/Config/Definition/Builder/NodeDefinition.php
+++ b/src/Symfony/Component/Config/Definition/Builder/NodeDefinition.php
@@ -364,7 +364,7 @@ abstract class NodeDefinition implements NodeParentInterface
                     $child->setPathSeparator($separator);
                 }
             } else {
-                @trigger_error('Passing a ParentNodeDefinitionInterface without getChildNodeDefinitions() is deprecated since Symfony 4.1.', E_USER_DEPRECATED);
+                @trigger_error(sprintf('Not implementing the "%s::getChildNodeDefinitions()" method in "%s" is deprecated since Symfony 4.1.', ParentNodeDefinitionInterface::class, \get_class($this)), E_USER_DEPRECATED);
             }
         }
 
diff --git a/src/Symfony/Component/Form/AbstractExtension.php b/src/Symfony/Component/Form/AbstractExtension.php
index c49edb7c70..ef26924a59 100644
--- a/src/Symfony/Component/Form/AbstractExtension.php
+++ b/src/Symfony/Component/Form/AbstractExtension.php
@@ -182,7 +182,7 @@ abstract class AbstractExtension implements FormExtensionInterface
                     $extendedTypes[] = $extendedType;
                 }
             } else {
-                @trigger_error(sprintf('Not implementing the static getExtendedTypes() method in %s when implementing the %s is deprecated since Symfony 4.2. The method will be added to the interface in 5.0.', \get_class($extension), FormTypeExtensionInterface::class), E_USER_DEPRECATED);
+                @trigger_error(sprintf('Not implementing the "%s::getExtendedTypes()" method in "%s" is deprecated since Symfony 4.2.', FormTypeExtensionInterface::class, \get_class($extension)), E_USER_DEPRECATED);
 
                 $extendedTypes = [$extension->getExtendedType()];
             }
diff --git a/src/Symfony/Component/Form/DependencyInjection/FormPass.php b/src/Symfony/Component/Form/DependencyInjection/FormPass.php
index f3cb08577e..7e10a5b13f 100644
--- a/src/Symfony/Component/Form/DependencyInjection/FormPass.php
+++ b/src/Symfony/Component/Form/DependencyInjection/FormPass.php
@@ -96,7 +96,7 @@ class FormPass implements CompilerPassInterface
 
             if (isset($tag[0]['extended_type'])) {
                 if (!method_exists($typeExtensionClass, 'getExtendedTypes')) {
-                    @trigger_error(sprintf('Not implementing the static getExtendedTypes() method in %s when implementing the %s is deprecated since Symfony 4.2. The method will be added to the interface in 5.0.', $typeExtensionClass, FormTypeExtensionInterface::class), E_USER_DEPRECATED);
+                    @trigger_error(sprintf('Not implementing the "%s::getExtendedTypes()" method in "%s" is deprecated since Symfony 4.2.', FormTypeExtensionInterface::class, $typeExtensionClass), E_USER_DEPRECATED);
                 }
 
                 $typeExtensions[$tag[0]['extended_type']][] = new Reference($serviceId);
diff --git a/src/Symfony/Component/Form/PreloadedExtension.php b/src/Symfony/Component/Form/PreloadedExtension.php
index ce0083234e..1e3f364831 100644
--- a/src/Symfony/Component/Form/PreloadedExtension.php
+++ b/src/Symfony/Component/Form/PreloadedExtension.php
@@ -36,7 +36,7 @@ class PreloadedExtension implements FormExtensionInterface
         foreach ($typeExtensions as $extensions) {
             foreach ($extensions as $typeExtension) {
                 if (!method_exists($typeExtension, 'getExtendedTypes')) {
-                    @trigger_error(sprintf('Not implementing the static getExtendedTypes() method in %s when implementing the %s is deprecated since Symfony 4.2. The method will be added to the interface in 5.0.', \get_class($typeExtension), FormTypeExtensionInterface::class), E_USER_DEPRECATED);
+                    @trigger_error(sprintf('Not implementing the "%s::getExtendedTypes()" method in "%s" is deprecated since Symfony 4.2.', FormTypeExtensionInterface::class, \get_class($typeExtension)), E_USER_DEPRECATED);
                 }
             }
         }
diff --git a/src/Symfony/Component/Intl/Tests/ResourceBundleTestCase.php b/src/Symfony/Component/Intl/Tests/ResourceBundleTestCase.php
index abb4e4d2ea..36940163f4 100644
--- a/src/Symfony/Component/Intl/Tests/ResourceBundleTestCase.php
+++ b/src/Symfony/Component/Intl/Tests/ResourceBundleTestCase.php
@@ -12,10 +12,13 @@
 namespace Symfony\Component\Intl\Tests;
 
 use PHPUnit\Framework\TestCase;
+use Symfony\Bridge\PhpUnit\ForwardCompatTestTrait;
 use Symfony\Component\Intl\Locale;
 
 abstract class ResourceBundleTestCase extends TestCase
 {
+    use ForwardCompatTestTrait;
+
     // Include the locales statically so that the data providers are decoupled
     // from the Intl class. Otherwise tests will fail if the intl extension is
     // not loaded, because it is NOT possible to skip the execution of data
@@ -696,7 +699,7 @@ abstract class ResourceBundleTestCase extends TestCase
 
     private static $rootLocales;
 
-    protected function setUp(): void
+    private function doSetUp()
     {
         Locale::setDefault('en');
         Locale::setDefaultFallback('en');
diff --git a/src/Symfony/Component/Security/Core/Authentication/Token/Storage/TokenStorage.php b/src/Symfony/Component/Security/Core/Authentication/Token/Storage/TokenStorage.php
index 97534b8f70..1b10bc219e 100644
--- a/src/Symfony/Component/Security/Core/Authentication/Token/Storage/TokenStorage.php
+++ b/src/Symfony/Component/Security/Core/Authentication/Token/Storage/TokenStorage.php
@@ -40,7 +40,7 @@ class TokenStorage implements TokenStorageInterface, ResetInterface
     public function setToken(TokenInterface $token = null)
     {
         if (null !== $token && !method_exists($token, 'getRoleNames')) {
-            @trigger_error(sprintf('Not implementing the getRoleNames() method in %s which implements %s is deprecated since Symfony 4.3.', \get_class($token), TokenInterface::class), E_USER_DEPRECATED);
+            @trigger_error(sprintf('Not implementing the "%s::getRoleNames()" method in "%s" is deprecated since Symfony 4.3.', TokenInterface::class, \get_class($token)), E_USER_DEPRECATED);
         }
 
         $this->token = $token;
diff --git a/src/Symfony/Component/Security/Core/Authorization/Voter/ExpressionVoter.php b/src/Symfony/Component/Security/Core/Authorization/Voter/ExpressionVoter.php
index e35583555d..0e1074b7c4 100644
--- a/src/Symfony/Component/Security/Core/Authorization/Voter/ExpressionVoter.php
+++ b/src/Symfony/Component/Security/Core/Authorization/Voter/ExpressionVoter.php
@@ -44,7 +44,7 @@ class ExpressionVoter implements VoterInterface
             $authChecker = null;
 
             if (!method_exists($roleHierarchy, 'getReachableRoleNames')) {
-                @trigger_error(sprintf('Not implementing the getReachableRoleNames() method in %s which implements %s is deprecated since Symfony 4.3.', \get_class($this->roleHierarchy), RoleHierarchyInterface::class), E_USER_DEPRECATED);
+                @trigger_error(sprintf('Not implementing the "%s::getReachableRoleNames()" method in "%s" is deprecated since Symfony 4.3.', RoleHierarchyInterface::class, \get_class($this->roleHierarchy)), E_USER_DEPRECATED);
             }
         } elseif (null === $authChecker) {
             @trigger_error(sprintf('Argument 3 passed to "%s()" should be an instance of AuthorizationCheckerInterface, not passing it is deprecated since Symfony 4.2.', __METHOD__), E_USER_DEPRECATED);
@@ -99,7 +99,7 @@ class ExpressionVoter implements VoterInterface
             $roleNames = $token->getRoleNames();
             $roles = array_map(function (string $role) { return new Role($role, false); }, $roleNames);
         } else {
-            @trigger_error(sprintf('Not implementing the getRoleNames() method in %s which implements %s is deprecated since Symfony 4.3.', \get_class($token), TokenInterface::class), E_USER_DEPRECATED);
+            @trigger_error(sprintf('Not implementing the "%s::getRoleNames()" method in "%s" is deprecated since Symfony 4.3.', TokenInterface::class, \get_class($token)), E_USER_DEPRECATED);
 
             $roles = $token->getRoles(false);
             $roleNames = array_map(function (Role $role) { return $role->getRole(); }, $roles);
diff --git a/src/Symfony/Component/Security/Core/Authorization/Voter/RoleHierarchyVoter.php b/src/Symfony/Component/Security/Core/Authorization/Voter/RoleHierarchyVoter.php
index d4524667c5..18b624078d 100644
--- a/src/Symfony/Component/Security/Core/Authorization/Voter/RoleHierarchyVoter.php
+++ b/src/Symfony/Component/Security/Core/Authorization/Voter/RoleHierarchyVoter.php
@@ -29,7 +29,7 @@ class RoleHierarchyVoter extends RoleVoter
     public function __construct(RoleHierarchyInterface $roleHierarchy, string $prefix = 'ROLE_')
     {
         if (!method_exists($roleHierarchy, 'getReachableRoleNames')) {
-            @trigger_error(sprintf('Not implementing the getReachableRoleNames() method in %s which implements %s is deprecated since Symfony 4.3.', \get_class($roleHierarchy), RoleHierarchyInterface::class), E_USER_DEPRECATED);
+            @trigger_error(sprintf('Not implementing the "%s::getReachableRoleNames()" method in "%s" is deprecated since Symfony 4.3.', RoleHierarchyInterface::class, \get_class($roleHierarchy)), E_USER_DEPRECATED);
         }
 
         $this->roleHierarchy = $roleHierarchy;
@@ -46,7 +46,7 @@ class RoleHierarchyVoter extends RoleVoter
             if (method_exists($token, 'getRoleNames')) {
                 $roles = $token->getRoleNames();
             } else {
-                @trigger_error(sprintf('Not implementing the getRoleNames() method in %s which implements %s is deprecated since Symfony 4.3.', \get_class($token), TokenInterface::class), E_USER_DEPRECATED);
+                @trigger_error(sprintf('Not implementing the "%s::getRoleNames()" method in "%s" is deprecated since Symfony 4.3.', TokenInterface::class, \get_class($token)), E_USER_DEPRECATED);
 
                 $roles = array_map(function (Role $role) { return $role->getRole(); }, $token->getRoles(false));
             }
diff --git a/src/Symfony/Component/Security/Core/Authorization/Voter/RoleVoter.php b/src/Symfony/Component/Security/Core/Authorization/Voter/RoleVoter.php
index deb542255c..776b2c80ce 100644
--- a/src/Symfony/Component/Security/Core/Authorization/Voter/RoleVoter.php
+++ b/src/Symfony/Component/Security/Core/Authorization/Voter/RoleVoter.php
@@ -62,7 +62,7 @@ class RoleVoter implements VoterInterface
             return $token->getRoleNames();
         }
 
-        @trigger_error(sprintf('Not implementing the getRoleNames() method in %s which implements %s is deprecated since Symfony 4.3.', \get_class($token), TokenInterface::class), E_USER_DEPRECATED);
+        @trigger_error(sprintf('Not implementing the "%s::getRoleNames()" method in "%s" is deprecated since Symfony 4.3.', TokenInterface::class, \get_class($token)), E_USER_DEPRECATED);
 
         return array_map(function (Role $role) { return $role->getRole(); }, $token->getRoles(false));
     }
diff --git a/src/Symfony/Component/Workflow/EventListener/GuardListener.php b/src/Symfony/Component/Workflow/EventListener/GuardListener.php
index 669d394a43..70c77a3402 100644
--- a/src/Symfony/Component/Workflow/EventListener/GuardListener.php
+++ b/src/Symfony/Component/Workflow/EventListener/GuardListener.php
@@ -38,7 +38,7 @@ class GuardListener
     public function __construct(array $configuration, ExpressionLanguage $expressionLanguage, TokenStorageInterface $tokenStorage, AuthorizationCheckerInterface $authorizationChecker, AuthenticationTrustResolverInterface $trustResolver, RoleHierarchyInterface $roleHierarchy = null, ValidatorInterface $validator = null)
     {
         if (null !== $roleHierarchy && !method_exists($roleHierarchy, 'getReachableRoleNames')) {
-            @trigger_error(sprintf('Not implementing the getReachableRoleNames() method in %s which implements %s is deprecated since Symfony 4.3.', \get_class($roleHierarchy), RoleHierarchyInterface::class), E_USER_DEPRECATED);
+            @trigger_error(sprintf('Not implementing the "%s::getReachableRoleNames()" method in "%s" is deprecated since Symfony 4.3.', RoleHierarchyInterface::class, \get_class($roleHierarchy)), E_USER_DEPRECATED);
         }
 
         $this->configuration = $configuration;
@@ -90,7 +90,7 @@ class GuardListener
             $roleNames = $token->getRoleNames();
             $roles = array_map(function (string $role) { return new Role($role, false); }, $roleNames);
         } else {
-            @trigger_error(sprintf('Not implementing the getRoleNames() method in %s which implements %s is deprecated since Symfony 4.3.', \get_class($token), TokenInterface::class), E_USER_DEPRECATED);
+            @trigger_error(sprintf('Not implementing the "%s::getRoleNames()" method in "%s" is deprecated since Symfony 4.3.', TokenInterface::class, \get_class($token)), E_USER_DEPRECATED);
 
             $roles = $token->getRoles(false);
             $roleNames = array_map(function (Role $role) { return $role->getRole(); }, $roles);