[clang] [lld] [llvm] [llvm][lld][clang] Delay initializing TargetOptions in LTO builds until a Triple is available (PR #179509)

[Paul Kirth via cfe-commits]

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@@ -47,7 +47,9 @@ struct Config {
   // Note: when adding fields here, consider whether they need to be added to
   // computeLTOCacheKey in LTO.cpp.
   std::string CPU;
-  TargetOptions Options;
+  // Callback to modify the target options once they are instantiated.
+  std::function<void(TargetOptions &Options)> ModifyTargetOptions =
+      [](TargetOptions &) {};
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ilovepi wrote:

Oh, I see. Yeah, that does make sense. I thought there was one place where the callback was issued much later on a TargetOption that had already been created/modified, but I'm not seeing it now. Let me try that, since it would make it clear that this *needs* the triple.

https://github.com/llvm/llvm-project/pull/179509