diff --git a/generator/config/CustomPhpStanFunctionMap.php b/generator/config/CustomPhpStanFunctionMap.php
index 241488ec..22ad1a21 100644
--- a/generator/config/CustomPhpStanFunctionMap.php
+++ b/generator/config/CustomPhpStanFunctionMap.php
@@ -6,6 +6,7 @@
  */
 
 return [
+    'base64_decode' => ['string|false', 'str'=>'string', 'strict='=>'bool'], // base64_decode returns false only in strict mode https://github.com/phpstan/phpstan-src/commit/cee66721266ae05f3cc052f82391d2645d74d55f
     'password_hash' => ['string|false', 'password'=>'string', 'algo'=>'int|string|null', 'options='=>'array'],
     'com_load_typelib' => ['bool', 'typelib_name'=>'string', 'case_insensitive='=>'bool'], // case_insensitive is a bool
     'sem_get' => ['resource|false', 'key'=>'int', 'max_acquire='=>'int', 'perm='=>'int', 'auto_release='=>'bool'], // auto_release is a bool