http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56028
--- Comment #1 from Uros Bizjak <ubizjak at gmail dot com> 2013-01-18 11:09:42 UTC --- - Does language standard guarantee atomic store in this case [wikipedia says "No." [1]]? - Can a store to a volatile DImode location be implemented as two consecutive SImode stores to adjacent location (this breaks stores of 64bit immediates to MMIO 64bit registers)? [1] http://en.wikipedia.org/wiki/Volatile_variable#In_C_and_C.2B.2B
