Revert "Driver: Objective-C should respect -fno-exceptions"

This reverts commit r223455.  It's been succesfully argued that
-fexceptions (at the driver level) is a misnomer and has little to do
with -fobjc-exceptions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@223723 91177308-0d34-0410-b5e6-96231b3b80d8
[modules] If the same .pcm file is imported via two different paths, don't
complain that the contained modules are defined twice.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@223724 91177308-0d34-0410-b5e6-96231b3b80d8
DebugInfo: Correctly identify the location of C++ member initializer list elements

This particularly helps the fidelity of ASan reports (which can occur
even in these examples - if, for example, one uses placement new over a
buffer of insufficient size - now ASan will correctly identify which
member's initialization went over the end of the buffer).

This doesn't cover all types of members - more coming.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@223726 91177308-0d34-0410-b5e6-96231b3b80d8