[llvm] [DebugInfo][DWARF] Bounds-check the unit-index parallel table (PR #213285)

[David Spickett via llvm-commits]

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@@ -159,6 +159,8 @@ bool DWARFUnitIndex::parseImpl(DataExtractor IndexData) {
     auto Index = IndexData.getU32(&Offset);
     if (!Index)
       continue;
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DavidSpickett wrote:

(do not address this in the same PR, but)

I wonder if we have another problem if there are not enough Indexes or there are duplicate indexes. As the part below "// Read Table of Section Offsets" assumes that Contribs[i] is non-null.

https://github.com/llvm/llvm-project/pull/213285