ArrayRefize code. No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180632 91177308-0d34-0410-b5e6-96231b3b80d8
[frontend] Make -chain-include work when used with modules.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180633 91177308-0d34-0410-b5e6-96231b3b80d8
[Modules] Fix an issue where the reconstructed redeclaration chain was incomplete, missing the definition from a module.

-Make sure that a deserialized external decl gets added to the TU scope.
-When associating an identifier with a set of decls, use the most recent local ones,
  if they exist, otherwise associating decls from modules (that came after a local one)
  will lead to an incomplete reconstructed re-declaration chain.

rdar://13712705

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180634 91177308-0d34-0410-b5e6-96231b3b80d8
[PCH/modules] Require the preprocessing record option to match the used PCH, if modules are enabled.

The preprocessing record becomes important when modules are enabled, since it is used to calculate the
module cache hash.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180635 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] Consolidate BoolAssignmentChecker tests by using two RUN lines.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180637 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] Model casts to bool differently from other numbers.

Casts to bool (and _Bool) are equivalent to checks against zero,
not truncations to 1 bit or 8 bits.

This improved reasoning does cause a change in the behavior of the alpha
BoolAssignment checker. Previously, this checker complained about statements
like "bool x = y" if 'y' was known not to be 0 or 1. Now it does not, since
that conversion is well-defined. It's hard to say what the "best" behavior
here is: this conversion is safe, but might be better written as an explicit
comparison against zero.

More usefully, besides improving our model of booleans, this fixes spurious
warnings when returning the address of a local variable cast to bool.

<rdar://problem/13296133>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180638 91177308-0d34-0410-b5e6-96231b3b80d8
[analyzer] An ObjC for-in loop runs 0 times if the collection is nil.

In an Objective-C for-in loop "for (id element in collection) {}", the loop
will run 0 times if the collection is nil. This is because the for-in loop
is implemented using a protocol method that returns 0 when there are no
elements to iterate, and messages to nil will result in a 0 return value.

At some point we may want to actually model this message send, but for now
we may as well get the nil case correct, and avoid the false positives that
would come with this case.

<rdar://problem/13744632>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180639 91177308-0d34-0410-b5e6-96231b3b80d8