pkgs/unix_api/src/handwritten_constants.h - labs - Git at Google

 // Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 __attribute__((visibility("default"))) __attribute__((used))
 void* libc_shim_get_MAP_FAILED(void);
	// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	__attribute__((visibility("default"))) __attribute__((used))
	void* libc_shim_get_MAP_FAILED(void);