| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // UNSUPPORTED: libcpp-has-no-stdin, libcpp-has-no-stdout |
| |
| // Make sure that the iostreams are initialized before everything else. |
| // This has been an issue when statically linking libc++ in some contexts. |
| // See https://llvm.org/PR28954 for details. |
| // |
| // This test works by checking that std::{cin,cout,cerr} is the same in a |
| // static object constructor and in the main function. It dumps the memory of |
| // each stream in the static object constructor and compares it with the memory |
| // in the main function. |
| // |
| // The assumption is that if there are no uses of the stream object (such as |
| // construction), then its memory must be the same. In the case where the test |
| // "fails" and we are actually accessing an uninitialized object when we perform |
| // the memcpy, the behavior is technically undefined (so the test could still |
| // pass). |
| |
| #include <cassert> |
| #include <cstring> |
| #include <iostream> |
| |
| struct Checker { |
| char *cerr_mem_dump; |
| char *cin_mem_dump; |
| char *cout_mem_dump; |
| char *clog_mem_dump; |
| |
| char *wcerr_mem_dump; |
| char *wcin_mem_dump; |
| char *wcout_mem_dump; |
| char *wclog_mem_dump; |
| |
| Checker() |
| : cerr_mem_dump(new char[sizeof(std::cerr)]) |
| , cin_mem_dump(new char[sizeof(std::cin)]) |
| , cout_mem_dump(new char[sizeof(std::cout)]) |
| , clog_mem_dump(new char[sizeof(std::clog)]) |
| |
| , wcerr_mem_dump(new char[sizeof(std::wcerr)]) |
| , wcin_mem_dump(new char[sizeof(std::wcin)]) |
| , wcout_mem_dump(new char[sizeof(std::wcout)]) |
| , wclog_mem_dump(new char[sizeof(std::wclog)]) |
| { |
| std::memcpy(cerr_mem_dump, (char*)&std::cerr, sizeof(std::cerr)); |
| std::memcpy(cin_mem_dump, (char*)&std::cin, sizeof(std::cin)); |
| std::memcpy(cout_mem_dump, (char*)&std::cout, sizeof(std::cout)); |
| std::memcpy(clog_mem_dump, (char*)&std::clog, sizeof(std::clog)); |
| |
| std::memcpy(wcerr_mem_dump, (char*)&std::wcerr, sizeof(std::wcerr)); |
| std::memcpy(wcin_mem_dump, (char*)&std::wcin, sizeof(std::wcin)); |
| std::memcpy(wcout_mem_dump, (char*)&std::wcout, sizeof(std::wcout)); |
| std::memcpy(wclog_mem_dump, (char*)&std::wclog, sizeof(std::wclog)); |
| } |
| |
| ~Checker() { |
| delete[] cerr_mem_dump; |
| delete[] cin_mem_dump; |
| delete[] cout_mem_dump; |
| delete[] clog_mem_dump; |
| |
| delete[] wcerr_mem_dump; |
| delete[] wcin_mem_dump; |
| delete[] wcout_mem_dump; |
| delete[] wclog_mem_dump; |
| } |
| }; |
| |
| static Checker check; |
| |
| int main(int, char**) { |
| assert(std::memcmp(check.cerr_mem_dump, (char const*)&std::cerr, sizeof(std::cerr)) == 0); |
| assert(std::memcmp(check.cin_mem_dump, (char const*)&std::cin, sizeof(std::cin)) == 0); |
| assert(std::memcmp(check.cout_mem_dump, (char const*)&std::cout, sizeof(std::cout)) == 0); |
| assert(std::memcmp(check.clog_mem_dump, (char const*)&std::clog, sizeof(std::clog)) == 0); |
| |
| assert(std::memcmp(check.wcerr_mem_dump, (char const*)&std::wcerr, sizeof(std::wcerr)) == 0); |
| assert(std::memcmp(check.wcin_mem_dump, (char const*)&std::wcin, sizeof(std::wcin)) == 0); |
| assert(std::memcmp(check.wcout_mem_dump, (char const*)&std::wcout, sizeof(std::wcout)) == 0); |
| assert(std::memcmp(check.wclog_mem_dump, (char const*)&std::wclog, sizeof(std::wclog)) == 0); |
| return 0; |
| } |