[clang] [clang] Allow no trivial before C++ module directive (PR #153641)

[Erich Keane via cfe-commits]

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@@ -1682,3 +1688,37 @@ const char *Preprocessor::getCheckPoint(FileID FID, const char *Start) const {
 
   return nullptr;
 }
+
+/// Whether allow C++ module directive.
+bool Preprocessor::hasSeenNoTrivialPPDirective() const {
+  return DirTracer && DirTracer->hasSeenNoTrivialPPDirective();
+}
+
+bool TrivialDirectiveTracer::hasSeenNoTrivialPPDirective() const {
+  return SeenNoTrivialPPDirective;
+}
+
+void TrivialDirectiveTracer::setSeenNoTrivialPPDirective(bool Val) {
+  if (InMainFile && !SeenNoTrivialPPDirective && Val)
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erichkeane wrote:

Yes, exactly my thoughts.  Just not call anything in those cases.

https://github.com/llvm/llvm-project/pull/153641