[PATCH] -fms-extensions: Implement half of #pragma init_seg

[Nico Weber]

================
Comment at: include/clang/Basic/AttrDocs.td:44
@@ +43,3 @@
+which global initialization function pointers are emitted.  It is only
+vailable with ``-fms-extensions``.  Typically, this function pointer is
+emitted into ``.CRT$XCU`` on Windows.  The user can change the order of
----------------
typo vailable

http://reviews.llvm.org/D4549