[clang] [clang-repl] Teach clang-repl how to load PCHs. (PR #94166)

[Aaron Ballman via cfe-commits]

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@@ -282,6 +288,8 @@ namespace {
     }
 
     void HandleTranslationUnit(ASTContext &Ctx) override {
+      IRGenFinished = true;
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AaronBallman wrote:

shouldn't this be set at the end of `HandleTranslationUnit` rather than the beginning?

https://github.com/llvm/llvm-project/pull/94166