[clang] [WIP][Safe Buffers] Serialize unsafe_buffer_usage pragmas (PR #92031)

[Artem Dergachev via cfe-commits]

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@@ -1551,6 +1567,58 @@ bool Preprocessor::isPPInSafeBufferOptOutRegion(SourceLocation &StartLoc) {
   return InSafeBufferOptOutRegion;
 }
 
+SmallVector<SourceLocation, 64>
+Preprocessor::serializeSafeBufferOptOutMap() const {
+  assert(!InSafeBufferOptOutRegion &&
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haoNoQ wrote:

We require the pragma to be closed before the end of TU right? And that's a hard error, not a warning?

https://github.com/llvm/llvm-project/pull/92031