- Outlaw duplicate input files, fix driver, fix tests, and add test.
- Reflect that no buffer is present without a (possibly pseudo) named file.
- Reflect fact that every input has a (possible pseudo) name.
- Break up CompilerInstance::setup.
Don't bail on dups.
Previously, we had hacks in place to eagerly emit everything in
the global ExternalDefinitions list. These can now be removed,
at least at the IRGen layer.
IRGen emits lazily-emitted definitions after emitting Clang declarations.
So an internal function that references an Objective-C class global and
is itself referenced from after a public function can observe
a OBJC_CLASS_$_ global defined by Clang.
Use a similar strategy as the Clang patch, just bitcast the global if it
exists already.
Fixes <rdar://problem/23200656>.
Swift SVN r32845
