[lld] [LLD][ELF] Add --why-live flag to report GC liveness reason (PR #119279)

[via llvm-commits]

github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

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``````````bash
git-clang-format --diff 8942d5ee6f73f00b9ccb1a1e4c27d4ff43fc41fe e3b779b1d13bc2f0e66326fa03e18eb9da126165 --extensions cpp,h -- lld/ELF/Config.h lld/ELF/Driver.cpp lld/ELF/MarkLive.cpp
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<details>
<summary>
View the diff from clang-format here.
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``````````diff
diff --git a/lld/ELF/MarkLive.cpp b/lld/ELF/MarkLive.cpp
index 1f31c33c31..246ede4b06 100644
--- a/lld/ELF/MarkLive.cpp
+++ b/lld/ELF/MarkLive.cpp
@@ -231,7 +231,7 @@ void MarkLive<ELFT>::enqueue(InputSectionBase *sec, uint64_t offset,
     whyLive.try_emplace(sec, sym);
   } else {
     // Otherwise, the parent generically makes the section itself live.
-    //whyLive.try_emplace(sec, parent);
+    // whyLive.try_emplace(sec, parent);
   }
 
   // Add input section to the queue.
@@ -240,8 +240,8 @@ void MarkLive<ELFT>::enqueue(InputSectionBase *sec, uint64_t offset,
 }
 
 template <class ELFT> void MarkLive<ELFT>::printWhyLive(Symbol *s) const {
-  //if (!whyLive.contains(s))
-    //return;
+  // if (!whyLive.contains(s))
+  // return;
 
   auto msg = Msg(ctx);
 

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https://github.com/llvm/llvm-project/pull/119279