[Frontend] Factor AddUnmappedPath() out of AddPath() and simplify.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173871 91177308-0d34-0410-b5e6-96231b3b80d8
c: When checking on validity of sizeof passed as size of
argument to be memset, check for its type to be complete 
before calling Context.getTypeSize(PointeeTy) to prevent 
crash. // rdar://13081751.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173872 91177308-0d34-0410-b5e6-96231b3b80d8
Provide a fixit for constexpr non-static data members.

If the member has an initializer, assume it was probably intended to be static
and suggest/recover with that.

If the member doesn't have an initializer, assume it was probably intended to
be const instead of constexpr and suggest that.

(if the attempt to apply these changes fails, don't make any suggestion &
produce the same diagnostic experience as before. The only case where this can
come up that I know of is with a mutable constexpr with an initializer, since
mutable is incompatible with static (but it's already incompatible with
const anyway))

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173873 91177308-0d34-0410-b5e6-96231b3b80d8
[Sema] Constrain test added in r173873 with expected-error-re

Suggested in post-commit review by Richard Smith.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173880 91177308-0d34-0410-b5e6-96231b3b80d8
Don't warn about Unicode characters in -E mode.

People use the C preprocessor for things other than C files. Some of them
have Unicode characters. We shouldn't warn about Unicode characters
appearing outside of identifiers in this case.

There's not currently a way for the preprocessor to tell if it's in -E mode,
so I added a new flag, derived from the PreprocessorOutputOptions. This is
only used by the Unicode warnings for now, but could conceivably be used by
other warnings or even behavioral differences later.

<rdar://problem/13107323>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173881 91177308-0d34-0410-b5e6-96231b3b80d8