Minor fixes

src/Psalm/Config.php

@@ -1123,8 +1123,6 @@ class Config
     }
 
     /**
-     * @param  SimpleXMLElement<SimpleXMLElement> $extensions
-     *
      * @throws ConfigException if a Config file could not be found
      *
      * @return void

src/Psalm/Internal/Analyzer/Statements/Expression/Call/ArgumentAnalyzer.php

@@ -121,8 +121,9 @@ class ArgumentAnalyzer
         }
 
         if ($function_param->expect_variable
-            && $arg_value_type->hasLiteralString()
+            && $arg_value_type->isSingleStringLiteral()
             && !$arg->value instanceof PhpParser\Node\Scalar
+            && !$arg->value instanceof PhpParser\Node\Expr\ConstFetch
         ) {
             if (IssueBuffer::accepts(
                 new InvalidArgument(

src/Psalm/Internal/Stubs/CoreGenericFunctions.phpstub

@@ -667,7 +667,7 @@ function preg_replace_callback($search, $replace, $subject, int $limit = -1, &$c
  *        ) $matches
  * @return int
  */
-function preg_match_all($pattern, $replace, &$matches, int $flags = 1) {}
+function preg_match_all($pattern, $replace, &$matches = [], int $flags = 1) {}
 
 /**
  * @psalm-pure