CodeGen: FieldMemcpyizer didn't handle copies starting inside bitfields

It's possible to construct cases where the first field we are trying to
copy is in the middle of an IR field.  In some complicated cases, we
would fail to use an appropriate offset inside the object.  Earlier
builds of clang seemed to miscompile the code by copying an insufficient
number of bytes.  Up until now, we would assert: the copying offset was
insufficiently aligned.

This fixes PR21232.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219524 91177308-0d34-0410-b5e6-96231b3b80d8
Bugfix for predefined expressions in dependent context.
This bug break compilation with precompiled headers and predefined expressions in dependent context.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219525 91177308-0d34-0410-b5e6-96231b3b80d8
Make test more robust to appease build bots

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219526 91177308-0d34-0410-b5e6-96231b3b80d8
Remove a FIXME: use the ios_simulator_version_min linker option consistently.

This was previously only used when explicitly requested with a command line
option because it had to work with some old versions of the linker when it
was first introduced. That is ancient history now, and it should be safe to
use the correct option even when using the IPHONEOS_DEPLOYMENT_TARGET
environment variable to specify that the target is the iOS simulator.
Besides updating the test for this, I also added a few more tests for the
iOS linker options.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219527 91177308-0d34-0410-b5e6-96231b3b80d8