[Bug c/21419] [4.0/4.1 Regression] Accepts writting to const via asm

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |4.0.0 4.1.0
      Known to work|                            |3.4.0 3.3.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21419