By ignoring this pragma with a warning, we're essentially miscompiling
the user's program. WebKit / Blink use this pragma to disable dynamic
initialization and finalization of some static data, and running the
dtors crashes the program.
Error out for now, so that /fallback compiles the TU correctly with
MSVC. This pragma should be implemented some time this month, and we
can remove this hack.
llvm-svn: 205554
Reid Kleckner