[Bug preprocessor/69126] [6 regression] _Pragma does not apply if part of a macro

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69126

--- Comment #12 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
Patch posted here:
  https://gcc.gnu.org/ml/gcc-patches/2016-01/msg01212.html