Index: lib/Support/raw_ostream.cpp =================================================================== --- lib/Support/raw_ostream.cpp +++ lib/Support/raw_ostream.cpp @@ -473,7 +473,7 @@ // possible. if (!(Flags & sys::fs::F_Text)) sys::ChangeStdoutToBinary(); - return STDOUT_FILENO; + return dup(STDOUT_FILENO); } int FD; Index: unittests/Support/raw_ostream_test.cpp =================================================================== --- unittests/Support/raw_ostream_test.cpp +++ unittests/Support/raw_ostream_test.cpp @@ -9,6 +9,7 @@ #include "gtest/gtest.h" #include "llvm/ADT/SmallString.h" +#include "llvm/Support/FileSystem.h" #include "llvm/Support/Format.h" #include "llvm/Support/raw_ostream.h" @@ -330,4 +331,11 @@ "0007: 68 69 6a 6b 6c |hijkl|", format_bytes_with_ascii_str(B.take_front(12), 0, 7, 1)); } + +TEST(raw_fd_ostreamTest, multiple_raw_fd_ostream_to_stdout) { + std::error_code EC; + + { raw_fd_ostream("-", EC, sys::fs::OpenFlags::F_None); } + { raw_fd_ostream("-", EC, sys::fs::OpenFlags::F_None); } +} }