[llvm-branch-commits] [clang] [Serialization] No transitive identifier change (PR #92085)

[Jan Svoboda via llvm-branch-commits]

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@@ -124,7 +124,7 @@ struct HeaderFileInfo {
   /// This ID number will be non-zero when there is a controlling
   /// macro whose IdentifierInfo may not yet have been loaded from
   /// external storage.
-  unsigned ControllingMacroID = 0;
+  uint64_t ControllingMacroID = 0;
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jansvoboda11 wrote:

This increases the size of `HeaderFileInfo` from 32 to 40 bytes. Can we squash this member with `ControllingMacro` into some kind of tagged pointer & `uint64_t` union to save space?

https://github.com/llvm/llvm-project/pull/92085