[lld] [LLD] Add CLASS syntax to SECTIONS (PR #95323)

[Fangrui Song via llvm-commits]

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@@ -228,6 +234,10 @@ class InputSectionDescription : public SectionCommand {
   // SectionPatterns can be filtered with the INPUT_SECTION_FLAGS command.
   uint64_t withFlags;
   uint64_t withoutFlags;
+
+  // If present, input section matching uses class membership instead of file
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MaskRay wrote:

If non-empty, this indicates a CLASS(class_name) reference, and filePat/sectionPatterns are not used.

Suggest to move this after sectionPatterns to make it clear they are mutual exclusive.

https://github.com/llvm/llvm-project/pull/95323