[llvm] [llvm-strip] Remove empty SHT_GROUP sections. (PR #97141)

[Fangrui Song via llvm-commits]

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@@ -963,6 +963,8 @@ class GroupSection : public SectionBase {
       const DenseMap<SectionBase *, SectionBase *> &FromTo) override;
   void onRemove() override;
 
+  size_t getMembersCount() { return GroupMembers.size(); }
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MaskRay wrote:

`() const`

https://github.com/llvm/llvm-project/pull/97141