[llvm] [DebugInfo] Add num_extra_inhabitants to debug info (PR #112590)

[via llvm-commits]

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@@ -551,7 +555,7 @@ DIBuilder::createVariantPart(DIScope *Scope, StringRef Name, DIFile *File,
   auto *R = DICompositeType::get(
       VMContext, dwarf::DW_TAG_variant_part, Name, File, LineNumber,
       getNonCompileUnitScope(Scope), nullptr, SizeInBits, AlignInBits, 0, Flags,
-      Elements, 0, nullptr, nullptr, UniqueIdentifier, Discriminator);
+      Elements, 0, nullptr, nullptr, UniqueIdentifier, 0, Discriminator);
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zmodem wrote:

This looks wrong. `DICompositeType::get` takes the new `NumExtraInhabitants` parameter at the end. Your change is now passing 0 for Discriminator, Discriminator for the DataLocation parameter, etc. That broke rustc's test suite, see (parts of) https://crbug.com/377743159

Since `DICompositeType::get`'s `NumExtraInhabitants` was added at the end, and with a default value, no change here is necessary.

I've followed up in https://github.com/llvm/llvm-project/commit/546066e4f74d50c974248b0ed247f65ebf24b75c

https://github.com/llvm/llvm-project/pull/112590