[ASTUnit] Reset diag state when creating the ASTUnit.
A client could call this with a dirty diagnostic engine, don't crash.
llvm-svn: 292406
diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index d892996..8064da0 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -1879,6 +1879,7 @@
// We'll manage file buffers ourselves.
Invocation->getPreprocessorOpts().RetainRemappedFileBuffers = true;
Invocation->getFrontendOpts().DisableFree = false;
+ getDiagnostics().Reset();
ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts());
std::unique_ptr<llvm::MemoryBuffer> OverrideMainBuffer;