[clang] [clang-repl] Keep the first llvm::Module empty to avoid invalid memory access. (PR #89031)

[Jonas Hahnfeld via cfe-commits]

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@@ -224,11 +228,8 @@ IncrementalParser::IncrementalParser(Interpreter &Interp,
     return;                     // PTU.takeError();
   }
 
-  if (CodeGenerator *CG = getCodeGen()) {
-    std::unique_ptr<llvm::Module> M(CG->ReleaseModule());
-    CG->StartModule("incr_module_" + std::to_string(PTUs.size()),
-                    M->getContext());
-    PTU->TheModule = std::move(M);
+  if (getCodeGen()) {
+    PTU->TheModule = std::move(GenModule());
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hahnjo wrote:

Just to confirm my understanding of the change: this is an independent deduplication cleanup, right? 

https://github.com/llvm/llvm-project/pull/89031