[libclang] Fix crash when a #pragma diagnostic is included in the preamble.
A PCH file keeps track of #pragma diagnostics state; when loading the preamble, they conflicted
with the #pragma diagnostic state already present in the DiagnosticsEngine object due to
parsing the preamble.
Fix this by clearing the state of the DiagnosticsEngine object.
Fixes rdar://10363572 && http://llvm.org/PR11254.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@143644 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed