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

[Aaron Ballman via cfe-commits]

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@@ -138,6 +138,8 @@ namespace {
       assert(!M && "Replacing existing Module?");
       M.reset(new llvm::Module(ExpandModuleName(ModuleName, CodeGenOpts), C));
 
+      IRGenFinished = false;
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AaronBallman wrote:

Why is IR gen *finished* when we're just starting the module?

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