Make raw_fd_ostream consider itself the owner of STDOUT_FILENO when

constructed with an output filename of "-". In particular, allow the
file descriptor to be closed, and close the file descriptor in the
destructor if it hasn't been explicitly closed already, to ensure
that any write errors are detected.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111436 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Support/raw_ostream.cpp

@@ -377,14 +377,17 @@ raw_fd_ostream::raw_fd_ostream(const char *Filename, std::string &ErrorInfo,
 
   ErrorInfo.clear();
 
-  // Handle "-" as stdout.
+  // Handle "-" as stdout. Note that when we do this, we consider ourself
+  // the owner of stdout. This means that we can do things like close the
+  // file descriptor when we're done and set the "binary" flag globally.
   if (Filename[0] == '-' && Filename[1] == 0) {
     FD = STDOUT_FILENO;
     // If user requested binary then put stdout into binary mode if
     // possible.
     if (Flags & F_Binary)
       sys::Program::ChangeStdoutToBinary();
-    ShouldClose = false;
+    // Close stdout when we're done, to detect any output errors.
+    ShouldClose = true;
     return;
   }