diff --git a/phpunit/code/compiler_api/extension_clean_maps.php b/phpunit/code/compiler_api/extension_clean_maps.php
new file mode 100644
index 00000000..74dd0adb
--- /dev/null
+++ b/phpunit/code/compiler_api/extension_clean_maps.php
@@ -0,0 +1,6 @@
+<?php
+
+function main(): void
+{
+    echo "ok\n";
+}
diff --git a/phpunit/code/inheritance_const_visibility_widen.php b/phpunit/code/inheritance_const_visibility_widen.php
new file mode 100644
index 00000000..f08d9369
--- /dev/null
+++ b/phpunit/code/inheritance_const_visibility_widen.php
@@ -0,0 +1,11 @@
+<?php
+
+class InheritanceConstVisibilityWidenParent
+{
+    protected const VALUE = 1;
+}
+
+class InheritanceConstVisibilityWidenChild extends InheritanceConstVisibilityWidenParent
+{
+    public const VALUE = 2;
+}
diff --git a/phpunit/code/inheritance_private_const_redeclare.php b/phpunit/code/inheritance_private_const_redeclare.php
new file mode 100644
index 00000000..985f7619
--- /dev/null
+++ b/phpunit/code/inheritance_private_const_redeclare.php
@@ -0,0 +1,11 @@
+<?php
+
+class InheritancePrivateConstRedeclareParent
+{
+    private const int VALUE = 1;
+}
+
+class InheritancePrivateConstRedeclareChild extends InheritancePrivateConstRedeclareParent
+{
+    public const string VALUE = 'child';
+}
diff --git a/phpunit/code/inheritance_private_prop_redeclare.php b/phpunit/code/inheritance_private_prop_redeclare.php
new file mode 100644
index 00000000..89145665
--- /dev/null
+++ b/phpunit/code/inheritance_private_prop_redeclare.php
@@ -0,0 +1,11 @@
+<?php
+
+class InheritancePrivatePropRedeclareParent
+{
+    private int $value = 1;
+}
+
+class InheritancePrivatePropRedeclareChild extends InheritancePrivatePropRedeclareParent
+{
+    private string $value = 'child';
+}
diff --git a/phpunit/code/inheritance_prop_visibility_widen.php b/phpunit/code/inheritance_prop_visibility_widen.php
new file mode 100644
index 00000000..b1203ec8
--- /dev/null
+++ b/phpunit/code/inheritance_prop_visibility_widen.php
@@ -0,0 +1,11 @@
+<?php
+
+class InheritancePropVisibilityWidenParent
+{
+    protected int $value = 1;
+}
+
+class InheritancePropVisibilityWidenChild extends InheritancePropVisibilityWidenParent
+{
+    public int $value = 2;
+}
diff --git a/phpunit/code/inheritance_protected_child_const_access.php b/phpunit/code/inheritance_protected_child_const_access.php
new file mode 100644
index 00000000..4b8ba577
--- /dev/null
+++ b/phpunit/code/inheritance_protected_child_const_access.php
@@ -0,0 +1,14 @@
+<?php
+
+class InheritanceProtectedChildConstAccessParent
+{
+    public function readChild(): int
+    {
+        return InheritanceProtectedChildConstAccessChild::VALUE;
+    }
+}
+
+class InheritanceProtectedChildConstAccessChild extends InheritanceProtectedChildConstAccessParent
+{
+    protected const VALUE = 1;
+}
diff --git a/phpunit/code/inheritance_protected_child_method_access.php b/phpunit/code/inheritance_protected_child_method_access.php
new file mode 100644
index 00000000..8ccec61d
--- /dev/null
+++ b/phpunit/code/inheritance_protected_child_method_access.php
@@ -0,0 +1,16 @@
+<?php
+
+class InheritanceProtectedChildMethodAccessParent
+{
+    public function callChild(): void
+    {
+        InheritanceProtectedChildMethodAccessChild::run();
+    }
+}
+
+class InheritanceProtectedChildMethodAccessChild extends InheritanceProtectedChildMethodAccessParent
+{
+    protected static function run(): void
+    {
+    }
+}
diff --git a/phpunit/src/CompilerBaseApiTest.php b/phpunit/src/CompilerBaseApiTest.php
index 1dabcceb..30b2450b 100644
--- a/phpunit/src/CompilerBaseApiTest.php
+++ b/phpunit/src/CompilerBaseApiTest.php
@@ -422,6 +422,32 @@ YAML);
         $this->assertArrayNotHasKey('cxxflags', $options);
     }
 
+    public function testExtensionCleanClearsRuntimeMapsWithValidCpp(): void
+    {
+        global $translator;
+        $compiler = CompilerTest::create(ROOT_PATH);
+        $translator = $compiler;
+        $ref = new \ReflectionClass($compiler);
+        $buildMode = $ref->getProperty('buildMode');
+        $buildMode->setAccessible(true);
+        $buildMode->setValue($compiler, CompilerBase::BUILD_MODE_EXT);
+
+        $testFile = ROOT_PATH . '/phpunit/code/compiler_api/extension_clean_maps.php';
+        $compiler->addFiles([$testFile]);
+        $compiler->prepareFile($testFile);
+        $compiler->convertFile($testFile);
+        $extensionFile = $compiler->genExtension();
+        $code = file_get_contents($extensionFile);
+
+        $this->assertStringContainsString('#include <cstring>', $code);
+        $this->assertStringContainsString('std::memset(php_func_map, 0, sizeof(php_func_map));', $code);
+        $this->assertStringContainsString('std::memset(php_class_map, 0, sizeof(php_class_map));', $code);
+        $this->assertStringContainsString('std::memset(php_property_map, 0, sizeof(php_property_map));', $code);
+        $this->assertStringNotContainsString('func_map = {}', $code);
+        $this->assertStringNotContainsString('class_map = {}', $code);
+        $this->assertStringNotContainsString('property_map = {}', $code);
+    }
+
     public function testObjectiveCppCompileCommandOptionsKeepCppOptions(): void
     {
         $this->setPropertyValue('cxxStd', 'c++20');
diff --git a/phpunit/src/InheritanceErrorTest.php b/phpunit/src/InheritanceErrorTest.php
index ab54eac6..dcc38a33 100644
--- a/phpunit/src/InheritanceErrorTest.php
+++ b/phpunit/src/InheritanceErrorTest.php
@@ -78,6 +78,16 @@ class InheritanceErrorTest extends TestCase
         $this->assertCompiles('inheritance_error_visibility.php');
     }
 
+    public function testParentScopeMayAccessChildProtectedMethod()
+    {
+        $this->assertCompiles('inheritance_protected_child_method_access.php');
+    }
+
+    public function testParentScopeMayAccessChildProtectedConstant()
+    {
+        $this->assertCompiles('inheritance_protected_child_const_access.php');
+    }
+
     public function testMethodStaticMismatch()
     {
         $this->exec('must be compatible', 'inheritance_error_static.php');
@@ -123,6 +133,16 @@ class InheritanceErrorTest extends TestCase
         $this->exec('must be compatible', 'inheritance_error_prop_visibility.php');
     }
 
+    public function testPropertyVisibilityMayBeWidened()
+    {
+        $this->assertCompiles('inheritance_prop_visibility_widen.php');
+    }
+
+    public function testPrivateParentPropertyMayBeRedeclared()
+    {
+        $this->assertCompiles('inheritance_private_prop_redeclare.php');
+    }
+
     public function testConstantTypeMismatch()
     {
         $this->exec('must be compatible', 'inheritance_error_const_type.php');
@@ -133,6 +153,16 @@ class InheritanceErrorTest extends TestCase
         $this->exec('must be compatible', 'inheritance_error_const_visibility.php');
     }
 
+    public function testConstantVisibilityMayBeWidened()
+    {
+        $this->assertCompiles('inheritance_const_visibility_widen.php');
+    }
+
+    public function testPrivateParentConstantMayBeRedeclared()
+    {
+        $this->assertCompiles('inheritance_private_const_redeclare.php');
+    }
+
     public function testPropertyReadonlyMismatch()
     {
         $this->exec('must be compatible', 'inheritance_error_prop_readonly.php');
diff --git a/src/Php/CompilerBase.php b/src/Php/CompilerBase.php
index 4c928170..73608a11 100644
--- a/src/Php/CompilerBase.php
+++ b/src/Php/CompilerBase.php
@@ -5483,7 +5483,10 @@ class CompilerBase extends \PhpAot\Core\Translator
             if (!$this->classDef) {
                 return false;
             }
-            return $this->isInheritedFrom($this->classDef->getNamespacedName(false), $classDef->getNamespacedName(false));
+            return $this->canAccessProtectedProperty(
+                $this->classDef->getNamespacedName(false),
+                $classDef->getNamespacedName(false)
+            );
         }
         // 类外部调用，只允许调用 public 方法
         return true;
diff --git a/src/Php/Translator.php b/src/Php/Translator.php
index cfe04d6c..70ab0473 100644
--- a/src/Php/Translator.php
+++ b/src/Php/Translator.php
@@ -778,7 +778,8 @@ class Translator extends Preprocessor
         $this->genClassCeList();
         $this->indentLevel++;
 
-        $code = $this->genIncludeHeaderFiles();
+        $code = '#include <cstring>' . PHP_EOL;
+        $code .= $this->genIncludeHeaderFiles();
 
         if ($this->isBuildModeBin()) {
             $cliHeaders = [
@@ -1018,9 +1019,9 @@ CODE;
 
         // 扩展模式，需要在 RSHUTDOWN 阶段中清理函数、类、属性表
         if ($this->isBuildModeExt()) {
-            $code .= self::FUNC_MAP." = {}\n";
-            $code .= self::CLASS_MAP." = {}\n";
-            $code .= self::PROP_MAP." = {}\n";
+            $code .= 'std::memset(' . self::PREFIX . self::FUNC_MAP . ', 0, sizeof(' . self::PREFIX . self::FUNC_MAP . '));' . PHP_EOL;
+            $code .= 'std::memset(' . self::PREFIX . self::CLASS_MAP . ', 0, sizeof(' . self::PREFIX . self::CLASS_MAP . '));' . PHP_EOL;
+            $code .= 'std::memset(' . self::PREFIX . self::PROP_MAP . ', 0, sizeof(' . self::PREFIX . self::PROP_MAP . '));' . PHP_EOL;
         }
 
         $code .= '}' . PHP_EOL . PHP_EOL;
@@ -3421,12 +3422,15 @@ CODE;
             foreach ($this->classDef->properties as $name => $childProp) {
                 if ($chainNode->hasProperty($name)) {
                     $parentProp = $chainNode->getProperty($name);
+                    if ($parentProp->flags & Modifiers::PRIVATE) {
+                        continue;
+                    }
                     if ($childProp->type !== $parentProp->type || $childProp->class !== $parentProp->class) {
                         $this->fatalError($classStmt,
                             "Declaration of `{$className}::\${$name}` must be compatible " .
                             "with `{$parentClass}::\${$name}`");
                     }
-                    if (($childProp->flags & Modifiers::VISIBILITY_MASK) !== ($parentProp->flags & Modifiers::VISIBILITY_MASK)) {
+                    if ($this->getVisibilityRank($childProp->flags) < $this->getVisibilityRank($parentProp->flags)) {
                         $this->fatalError($classStmt,
                             "Declaration of `{$className}::\${$name}` must be compatible " .
                             "with `{$parentClass}::\${$name}`");
@@ -3455,12 +3459,15 @@ CODE;
             foreach ($this->classDef->constants as $name => $childConst) {
                 if ($chainNode->hasConstant($name)) {
                     $parentConst = $chainNode->getConstant($name);
+                    if ($parentConst->flags & Modifiers::PRIVATE) {
+                        continue;
+                    }
                     if ($childConst->type !== $parentConst->type || $childConst->class !== $parentConst->class) {
                         $this->fatalError($classStmt,
                             "Declaration of `{$className}::{$name}` must be compatible " .
                             "with `{$parentClass}::{$name}`");
                     }
-                    if (($childConst->flags & Modifiers::VISIBILITY_MASK) !== ($parentConst->flags & Modifiers::VISIBILITY_MASK)) {
+                    if ($this->getVisibilityRank($childConst->flags) < $this->getVisibilityRank($parentConst->flags)) {
                         $this->fatalError($classStmt,
                             "Declaration of `{$className}::{$name}` must be compatible " .
                             "with `{$parentClass}::{$name}`");