[clang] [clang-repl] Fix inconsistent flushing between in-process and out-of-process (PR #166368)

[Vassil Vassilev via cfe-commits]

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@@ -352,6 +352,20 @@ int main(int argc, const char **argv) {
     Interp = ExitOnErr(clang::Interpreter::create(std::move(CI), Config));
   }
 
+  if (Config.IsOutOfProcess) {
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vgvassilev wrote:

I think both setups have a flush problem.

https://github.com/llvm/llvm-project/pull/166368