simplify

Author: staabm

stubs/core.stub

@@ -364,13 +364,13 @@ function header_register_callback(callable $callback): bool {}
 function register_tick_function(callable $callback, mixed ...$args): bool {}
 
 /**
- * @template P of int = int
+ * @template P of int
  *
  * @param string|list<string> $command
  * @param array<P, list<string>|resource> $descriptor_spec
- * @param array<mixed> $pipes
- * @param array<string, mixed> $env_vars
- * @param array<string, bool> $options
+ * @param mixed $pipes
+ * @param null|array<string, mixed> $env_vars
+ * @param null|array<string, bool> $options
  *
  * @param-out array<P, resource> $pipes
  *