[lld] [llvm] [lld][AArch64][Build Attributes] Add support for converting AArch64 Build Attributes to GNU Properties (PR #131990)

[Peter Smith via llvm-commits]

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@@ -207,6 +209,51 @@ static void updateSupportedARMFeatures(Ctx &ctx,
   ctx.arg.armHasThumb2ISA |= thumb && *thumb >= ARMBuildAttrs::AllowThumb32;
 }
 
+struct KnownAArch64BuildAttrSubsections {
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smithp35 wrote:

I'd drop the `Known` and just use `AArch64BuildAttrSubSections`. It is highly unlikely that any private subsections will make it upstream.

https://github.com/llvm/llvm-project/pull/131990