[clang] [clang][driver] Add -mtls-dialect option (PR #79031)

[Fangrui Song via cfe-commits]

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@@ -401,6 +401,8 @@ static bool initTargetOptions(DiagnosticsEngine &Diags,
   Options.UniqueBasicBlockSectionNames =
       CodeGenOpts.UniqueBasicBlockSectionNames;
   Options.TLSSize = CodeGenOpts.TLSSize;
+  // TODO: Add correct codegen options in LLVM
+  // Options.TLSDesc = CodeGenOpts.getDefaultTLSDialect();
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MaskRay wrote:

This should be supported in this patch, otherwise there is no point in ignoring a rarely-used GCC option.

https://github.com/llvm/llvm-project/pull/79031