tree d599c71bb12d426f7b62685c62d185950219ab81
parent f5b132f7b373203eab7cf357b01f935bd88087bd
author Douglas Gregor <dgregor@apple.com> 1349798510 +0000
committer Douglas Gregor <dgregor@apple.com> 1349798510 +0000

If a macro has been #undef'd in a precompiled header, we still need to
write out the macro history for that macro. Similarly, we need to cope
with reading a macro definition that has been #undef'd.

Take advantage of this new ability so that global code-completion
results can refer to #undef'd macros, rather than losing them
entirely. For multiply defined/#undef'd macros, we will still get the
wrong result, but it's better than getting no result.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@165502 91177308-0d34-0410-b5e6-96231b3b80d8