Fix http://llvm.org/bugs/show_bug.cgi?id=11752

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@148069 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/fstream b/include/fstream
index 4456c01..8e1b1fb 100644
--- a/include/fstream
+++ b/include/fstream
@@ -549,7 +549,7 @@
     {
         __rt = this;
         unique_ptr<FILE, int(*)(FILE*)> __h(__file_, fclose);
-        if ((__cm_ & ios_base::out) && sync())
+        if (sync())
             __rt = 0;
         if (fclose(__h.release()) == 0)
             __file_ = 0;