[llvm] [CLANG][DWARF] Handle DIE offset collision in DW_IDX_parent (PR #95039)

[Alexander Yermolovich via llvm-commits]

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@@ -257,17 +257,37 @@ class AppleAccelTableData : public AccelTableData {
 
 /// Helper class to identify an entry in DWARF5AccelTable based on their DIE
 /// offset and UnitID.
-struct OffsetAndUnitID : std::pair<uint64_t, uint32_t> {
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ayermolo wrote:

I don't really have a strong opinion. Poking around I don't really see tuple being used with DenseMap. More standard approach seems this boilerplate code. 
@dwblaikie to break a tie? :)

https://github.com/llvm/llvm-project/pull/95039