[clang] [clang-tools-extra] [lld] [lldb] [llvm] [mlir] Rename llvm::ThreadPool -> llvm::DefaultThreadPool (NFC) (PR #83702)

[Mehdi Amini via cfe-commits]

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@@ -104,7 +104,7 @@ static std::recursive_mutex *g_debugger_list_mutex_ptr =
     nullptr; // NOTE: intentional leak to avoid issues with C++ destructor chain
 static Debugger::DebuggerList *g_debugger_list_ptr =
     nullptr; // NOTE: intentional leak to avoid issues with C++ destructor chain
-static llvm::ThreadPool *g_thread_pool = nullptr;
+static llvm::DefaultThreadPoolThreadPool *g_thread_pool = nullptr;
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joker-eph wrote:

Weirdly this issue wasn't caught in CI!

https://github.com/llvm/llvm-project/pull/83702