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

[Oliver Stannard via llvm-commits]

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@@ -207,6 +209,53 @@ static void updateSupportedARMFeatures(Ctx &ctx,
   ctx.arg.armHasThumb2ISA |= thumb && *thumb >= ARMBuildAttrs::AllowThumb32;
 }
 
+struct KnownAArch64BuildAttrSubsections {
+  struct PauthSubSection {
+    unsigned tagPlatform = 0;
+    unsigned tagSchema = 0;
+  } pauth;
+  struct FAndBSubSection {
+    unsigned tagBTI = 0;
+    unsigned tagPAC = 0;
+    unsigned tagGCS = 0;
+  } fAndB;
+};
+
+static KnownAArch64BuildAttrSubsections
+extractBuildAttributesSubsections(Ctx &ctx,
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ostannard wrote:

The `ctx` and `isec` arguments are unused (but see comment below, maybe this whole function can be removed).

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