feat(compiler): add constant declarations to global variable header

- Add assertion to verify _const_var_ is not in main header
- Generate extern declarations for constants in global variable header
- Include exported ABI constants in global header generation
- Move constant extern declarations from extension file to global header
- Add test cases for exported ABI integer, string, and array constants

phpunit/code/compiler_api/default_argument_abi.php

@@ -1,5 +1,9 @@
 <?php
 
+const EXPORTED_ABI_INT = 42;
+const EXPORTED_ABI_STRING = 'internal';
+const EXPORTED_ABI_ARRAY = ['mode' => 'fast'];
+
 function exported_defaults(
     string $text = 'hello',
     array $options = ['mode' => 'fast'],

phpunit/src/CompilerBaseApiTest.php

@@ -863,9 +863,19 @@ YAML);
             $header
         );
         $this->assertStringNotContainsString('_literal_strings', $header);
+        $this->assertStringNotContainsString('_const_var_', $header);
         $this->assertStringNotContainsString('php_func_map', $header);
         $this->assertStringNotContainsString('php_class_map', $header);
 
+        $globalHeaderFile = $this->testDir . '/php_abi_defaults_global_var_decl.h';
+        $this->compiler->genExternGlobalVars($globalHeaderFile);
+        $globalHeader = file_get_contents($globalHeaderFile);
+        $this->assertStringContainsString('extern php::Var _const_var_EXPORTED_ABI_INT;', $globalHeader);
+        $this->assertStringContainsString('extern php::Var _const_var_EXPORTED_ABI_STRING;', $globalHeader);
+        $this->assertStringContainsString('extern php::Var _const_var_EXPORTED_ABI_ARRAY;', $globalHeader);
+        $this->assertStringContainsString('extern php::Str _literal_strings[', $globalHeader);
+        $this->assertStringContainsString('extern THREAD_LOCAL zend_function *php_func_map[', $globalHeader);
+
         $extensionFile = $this->compiler->genExtension();
         $extension = file_get_contents($extensionFile);
         $this->assertStringContainsString('php::Str php_exported_defaults_arg_0_default_value() {', $extension);

src/Translator.php

@@ -669,6 +669,10 @@ class Translator extends Preprocessor
             $lines[] = 'extern ' . Type::STR . ' ' . self::LITERAL_STRINGS . '[' . $literalStringsCount . '];' . PHP_EOL;
         }
 
+        foreach ($this->constants as $name => $constant) {
+            $lines[] = 'extern ' . $constant->type . ' ' . $name . ';';
+        }
+
         // 确保数组大小至少为 1，避免 C/C++ 编译错误
         $classCount = max(1, count($this->classMap));
         $lines[] = 'extern THREAD_LOCAL zend_class_entry *' . self::PREFIX . self::CLASS_MAP . '[' . $classCount . '];' . PHP_EOL;
@@ -1590,10 +1594,6 @@ CODE;
             }
         }
 
-        $code .= PHP_EOL;
-        foreach ($this->constants as $name => $constant) {
-            $code .= 'extern ' . $constant->type . ' ' . $name . ';' . PHP_EOL;
-        }
         $this->writeFile($file, $code);
     }