Volodymyr Sapsai cdb50bc93b Revert "Emit an error when mixing <stdatomic.h> and <atomic>"
It reverts commit r331379 because turned out `__ALLOW_STDC_ATOMICS_IN_CXX__`
doesn't work well in practice.

llvm-svn: 331818
2018-05-08 22:50:35 +00:00
..
2018-02-08 05:47:40 +00:00