[clang] Fix --print-libgcc-file-name on Darwin platforms (PR #98325)

[Louis Dionne via cfe-commits]

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@@ -2271,6 +2271,12 @@ bool Driver::HandleImmediateArgs(const Compilation &C) {
   if (C.getArgs().hasArg(options::OPT_print_libgcc_file_name)) {
     ToolChain::RuntimeLibType RLT = TC.GetRuntimeLibType(C.getArgs());
     const llvm::Triple Triple(TC.ComputeEffectiveClangTriple(C.getArgs()));
+    // The 'Darwin' toolchain is initialized only when its arguments are
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ldionne wrote:

Could we do the same thing but move it way up above so that we initialize it early? I think the same bug exists with `-print-runtime-dir` (line 2232 above).

https://github.com/llvm/llvm-project/pull/98325