diff --git a/bin/compiler.php b/bin/compiler.php
index 08c3f00a..2d829cd6 100755
--- a/bin/compiler.php
+++ b/bin/compiler.php
@@ -1,6 +1,7 @@
 #!/usr/bin/env php
 <?php
 require __DIR__ . '/bootstrap.php';
+require __DIR__ . '/../src/gen_stub.php';
 
 use PhpAot\Php\Exception\SyntaxError;
 use PhpAot\Php\Exception\Unsupported;
diff --git a/examples/extends/A.php b/examples/extends/A.php
index 91fdd331..157680f0 100644
--- a/examples/extends/A.php
+++ b/examples/extends/A.php
@@ -1,8 +1,15 @@
 <?php
+
+
 class A extends Foo
 {
+    const FOO = PHP_OS;
+    const FOO2 = PHP_INT_SIZE;
+    const BAZ = self::INIT_STATE;
+
     public function __construct()
     {
+        var_dump(self::BAZ);
         echo "A::__construct()\n";
     }
 }
diff --git a/examples/extends/Foo.php b/examples/extends/Foo.php
index ea00ed33..3a209665 100644
--- a/examples/extends/Foo.php
+++ b/examples/extends/Foo.php
@@ -1,4 +1,4 @@
 <?php
 class Foo extends ArrayObject {
-
+    const INIT_STATE = 'init';
 }
\ No newline at end of file
diff --git a/src/Php/CompilerBase.php b/src/Php/CompilerBase.php
index d6925c06..5dd96b79 100644
--- a/src/Php/CompilerBase.php
+++ b/src/Php/CompilerBase.php
@@ -562,7 +562,7 @@ class CompilerBase extends \PhpAot\Core\Translator
         return false;
     }
 
-    protected function getRelativePath($path, $cwd = ''): string
+    public function getRelativePath($path, $cwd = ''): string
     {
         $cwd = $cwd ?: getcwd();
         return ltrim($this->removeCommonPrefix($cwd, $path), '/');
diff --git a/src/Php/Entity/ConstantDef.php b/src/Php/Entity/ConstantDef.php
index 550a1cab..cdbbfedf 100644
--- a/src/Php/Entity/ConstantDef.php
+++ b/src/Php/Entity/ConstantDef.php
@@ -8,6 +8,8 @@
 
 namespace PhpAot\Php\Entity;
 
+use PhpParser\NodeAbstract;
+
 class ConstantDef
 {
     public string $name;
@@ -16,6 +18,7 @@ class ConstantDef
     public string $value;
     public string $arrayExpr = '';
     public string $class = '';
+    public ?NodeAbstract $valueExpr = null;
 
     public function __construct(string $name, int $flags, string $type, string $value)
     {
diff --git a/src/Php/Generator/Utils.php b/src/Php/Generator/Utils.php
index 88e40035..13c72fa0 100644
--- a/src/Php/Generator/Utils.php
+++ b/src/Php/Generator/Utils.php
@@ -13,6 +13,17 @@ use PhpAot\Php\Constants;
 
 trait Utils
 {
+    protected function genCValue(mixed $value): mixed
+    {
+        if (is_int($value) or is_float($value)) {
+            return $value;
+        } elseif (is_string($value)) {
+            return $this->genCharPtr($value);
+        } else {
+            $this->error('Unsupported constant type: ' . gettype($value));
+        }
+    }
+
     protected function genCharPtr(string $str, bool $escape = false): string
     {
         return '"' . ($escape ? $this->escapeString($str) : $str) . '"';
diff --git a/src/Php/Preprocessor.php b/src/Php/Preprocessor.php
index 0a5b9841..1032a45d 100644
--- a/src/Php/Preprocessor.php
+++ b/src/Php/Preprocessor.php
@@ -518,6 +518,7 @@ class Preprocessor extends CompilerBase
             $constValue = $this->parseIdentifier($const->value);
 
             $constInfo = new ConstantDef($constName, $flags, $type, $constValue);
+            $constInfo->valueExpr = $const->value;
 
             if ($this->context->beforeStmtLines) {
                 $arrayExpr = '';
diff --git a/src/Php/Translator.php b/src/Php/Translator.php
index b196a6cb..e123428d 100644
--- a/src/Php/Translator.php
+++ b/src/Php/Translator.php
@@ -21,6 +21,7 @@ use PhpAot\Php\Exception\Unsupported;
 use PhpParser\Modifiers;
 use PhpParser\Node;
 use PhpParser\Node\Stmt\Foreach_;
+use PhpParser\NodeAbstract;
 use PhpParser\NodeTraverser;
 use Symfony\Component\Yaml\Yaml;
 
@@ -106,7 +107,6 @@ class Translator extends Preprocessor
             return $this->getCppFile($file);
         }
         $phpCode = $this->loadFile($file);
-        $this->genStubFile($this->file);
         $this->localHeaders = [];
         while (true) {
             try {
@@ -114,7 +114,8 @@ class Translator extends Preprocessor
                 $cppFile = $this->getCppFile($file);
                 $this->save($cppCode, $cppFile);
                 $this->phpSrcFiles[] = $file;
-
+                // 生成 stub 文件，依赖 convert 阶段的 use 等信息
+                $this->genStubFile($this->file);
                 return $cppFile;
             } catch (Redo $e) {
                 continue;
@@ -646,6 +647,11 @@ class Translator extends Preprocessor
         return $list;
     }
 
+    public function getDefinedConstants(): array
+    {
+        return $this->internalConstants;
+    }
+
     protected function getInternalCeInfo(string $ce): array
     {
         return [
@@ -856,14 +862,13 @@ class Translator extends Preprocessor
         $stubFilenameWithoutExtension = str_replace(['.stub.php', '.php'], '', $file);
         $headerFile = $this->getArgInfoHeaderFile($stubFilenameWithoutExtension, true);
 
-        $genStubCmd = PHP_BINARY . ' ' . $this->rootPath . '/bin/gen_stub.php -f -o ' . $this->getIncludeDir() . '/' . $headerFile . ' ' . $file;
-        $output = shell_exec($genStubCmd);
-        $this->climate->info('generate stub file: ' . $this->getRelativePath($file));
-        $this->climate->comment($genStubCmd);
-
-        if (!str_contains($output, 'Saved')) {
-            $this->error("failed to generate arginfo header file: `{$headerFile}`, output: {$output}");
+        try {
+            generateStubFile($file, $this->getIncludeDir() . '/' . $headerFile, true);
+        } catch (\Throwable $e) {
+            $this->error("failed to generate arginfo header file: `{$headerFile}`, Error: {$e->getMessage()}");
         }
+
+        $this->climate->info('generate stub file: ' . $this->getRelativePath($file));
         if ($this->useRegisterSymbolsFn) {
             preg_match('/php_(.*)_arginfo.h/', $headerFile, $matches);
             $registerSymbolFn = 'register_' . $matches[1] . '_symbols';
@@ -1301,4 +1306,48 @@ class Translator extends Preprocessor
 
         return $code;
     }
+
+    /**
+     * 仅用于 gen_stub 脚本
+     * @param NodeAbstract $expr
+     * @param string $class
+     * @param string $name
+     * @return mixed
+     * @throws \Exception
+     */
+    public function getClassConstValue(NodeAbstract $expr, string $class, string $name): mixed
+    {
+        $class = $this->getNamespacedClassName($class);
+        $nativeConst = $this->findNativeClassConst($expr, $class, $name);
+        if ($nativeConst and $expr->hasAttribute('nativeConst')) {
+            $constDef = $expr->getAttribute('nativeConst');
+            return $this->genCValue($constDef->valueExpr->value);
+        }
+        throw new \Exception("Class constant `$class::$name` not found");
+    }
+
+    public function getConstValue(string $name): mixed
+    {
+        if ($this->isInternalConstant($name)) {
+            $value = $this->internalConstants[$name];
+            if (is_int($value)) {
+                $expr = strval($value);
+                if ($value === PHP_INT_MIN) {
+                    $expr = 'LONG_MIN';
+                } elseif ($value === PHP_INT_MAX) {
+                    $expr = 'LONG_MAX';
+                } else {
+                    $expr = $expr . 'L';
+                }
+            } elseif (is_float($value)) {
+                return $value;
+            } elseif (is_string($value)) {
+                return $this->genCharPtr($value);
+            } else {
+                $this->error('Unsupported constant type: ' . gettype($value));
+            }
+            return $expr;
+        }
+        throw new \Exception('Constant ' . $name . ' not found');
+    }
 }
diff --git a/bin/gen_stub.php b/src/gen_stub.php
similarity index 99%
rename from bin/gen_stub.php
rename to src/gen_stub.php
index 0364cde8..87b817ea 100755
--- a/bin/gen_stub.php
+++ b/src/gen_stub.php
@@ -1,5 +1,5 @@
-#!/usr/bin/env php
-<?php declare(strict_types=1);
+<?php
+declare(strict_types=1);
 
 use PhpAot\Php\Translator;
 use PhpParser\Comment\Doc as DocComment;
@@ -37,9 +37,7 @@ const ALL_PHP_VERSION_IDS = [
 
 // file_put_contents() but with a success message printed after saving
 function reportFilePutContents(string $filename, string $content): void {
-    global $translator;
-    $translator->writeFile($filename, $content);
-    echo "Saved $filename\n";
+    getTranslator()->writeFile($filename, $content);
 }
 
 /**
@@ -149,8 +147,7 @@ function processStubFile(string $stubFile, Context $context, bool $includeOnly =
 
         return $fileInfo;
     } catch (Exception $e) {
-        echo "In $stubFile:\n{$e->getMessage()}\n";
-        exit(1);
+        throw new RuntimeException("In " . getTranslator()->getRelativePath($stubFile) . ": {$e->getMessage()}");
     }
 }
 
@@ -2309,7 +2306,7 @@ class EvaluatedValue
                         if (isset($allConstInfos[$constName])) {
                             return $allConstInfos[$constName]->getValue($allConstInfos)->value;
                         } else {
-                            throw new Exception("Class constant `$constName` not found");
+                            return getTranslator()->getClassConstValue($expr, ClassInfo::$currentClass->name->toString(), $expr->name->toString());
                         }
                     } elseif ($expr->name->__toString() === 'class') {
                         return $class;
@@ -2337,6 +2334,7 @@ class EvaluatedValue
                         } elseif ($constType->isFloat()) {
                             return M_PI;
                         } elseif ($constType->isString()) {
+                            var_dump($const);
                             return $const->name;
                         } elseif ($constType->isArray()) {
                             return [];
@@ -2346,7 +2344,7 @@ class EvaluatedValue
                     return null;
                 }
 
-                global $definedConstants;
+                $definedConstants = getTranslator()->getDefinedConstants();
                 if (isset($definedConstants[$constName])) {
                     $constValue = $definedConstants[$constName];
                     if (is_scalar($constValue)) {
@@ -2448,28 +2446,17 @@ class EvaluatedValue
                     $this->expr->name->__toString() === 'class') {
                     $expr = '"' . addcslashes($this->expr->class->name, '\\') . '"';
                 } else {
-                    var_dump($this->value);
+                    return $this->value;
                 }
             } elseif (!($this->expr instanceof String_)) {
+                if ($this->expr instanceof Expr\ConstFetch) {
+                    return getTranslator()->getConstValue($this->expr->name->toString());
+                }
                 throw new Exception("Expression at line " . $this->expr->getStartLine() . " must be a scalar string");
             }
             $expr = preg_replace("/(^'|'$)/", '"', $expr);
-        } elseif ($this->type->isInt() or $this->type->isFloat()) {
+        } elseif ($this->type->isInt() or $this->type->isFloat() or $this->expr instanceof Expr\ConstFetch) {
             return strval($this->value);
-        } else {
-            if ($this->expr instanceof Expr\ConstFetch) {
-                $value = constant($this->expr->name->__toString());
-                if (is_int($value)) {
-                    $expr = strval($value);
-                    if ($value === PHP_INT_MIN) {
-                        $expr = 'LONG_MIN';
-                    } elseif ($value === PHP_INT_MAX) {
-                        $expr = 'LONG_MAX';
-                    } else {
-                        $expr = $expr . 'L';
-                    }
-                }
-            }
         }
         return $expr[0] == '"' ? $expr : preg_replace('(\bnull\b)', 'NULL', str_replace('\\', '', $expr));
     }
@@ -6172,20 +6159,17 @@ function initPhpParser() {
     $isInitialized = true;
 }
 
-function main()
+function getTranslator(): Translator
 {
-    global $argv, $argc, $translator, $definedConstants;
-
-    error_reporting(E_ALL & ~E_DEPRECATED);
-    ini_set("precision", "-1");
-    require __DIR__ . '/bootstrap.php';
-
-    $translator = new PhpAot\Php\Translator(ROOT_PATH);
-    $translator->setIndent("\t");
-    $translator->setIndentLevel(1);
-
-    $definedConstants = get_defined_constants();
+    global $translator;
+    return $translator;
+}
 
+/**
+ * @throws Exception
+ */
+function generateStubFile(string $stubFile, string $objectFile, bool $forceRegeneration): void
+{
     $opt_index = 0;
     $options = getopt(
         "fho:",
@@ -6208,15 +6192,15 @@ function main()
     $replaceMethodSynopses = isset($options["replace-methodsynopses"]);
     $generateOptimizerInfo = isset($options["generate-optimizer-info"]);
 
-    $context->forceRegeneration = isset($options["f"]) || isset($options["force-regeneration"]);
-    $context->objectFile = $options["o"] ?? '';
+    $context->forceRegeneration = $forceRegeneration;
+    $context->objectFile = $objectFile;
     $context->forceParse = $context->forceRegeneration || $printParameterStats || $verify || $verifyManual || $replacePredefinedConstants || $generateClassSynopses || $generateOptimizerInfo || $replaceClassSynopses || $generateMethodSynopses || $replaceMethodSynopses;
 
     if (isset($options["h"]) || isset($options["help"])) {
         die("\nUsage: gen_stub.php [ -f | --force-regeneration ] [ --replace-predefined-constants ] [ --generate-classsynopses ] [ --replace-classsynopses ] [ --generate-methodsynopses ] [ --replace-methodsynopses ] [ --parameter-stats ] [ --verify ]  [ --verify-manual ] [ --generate-optimizer-info ] [ -h | --help ] [ name.stub.php | directory ] [ directory ]\n\n");
     }
 
-    $locations = array_slice($argv, $opt_index);
+    $locations = [$stubFile];
     $locationCount = count($locations);
     if ($replacePredefinedConstants && $locationCount < 2) {
         die("At least one source stub path and a target manual directory has to be provided:\n./build/gen_stub.php --replace-predefined-constants ./ ../doc-en/\n");
@@ -6388,10 +6372,8 @@ function main()
             }
         }
 
-        echo implode("\n", $errors);
         if (!empty($errors)) {
-            echo "\n";
-            exit(1);
+            throw new Exception("Errors found: " . implode("\n", $errors));
         }
     }
 
@@ -6492,5 +6474,3 @@ function main()
         }
     }
 }
-
-main();
\ No newline at end of file