[lld] [AArch64][GCS][LLD] Introduce -zgcs-report-dynamic Command Line Option (PR #127787)

[Fangrui Song via llvm-commits]

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@@ -136,6 +136,26 @@ enum LtoKind : uint8_t {UnifiedThin, UnifiedRegular, Default};
 // For -z gcs=
 enum class GcsPolicy { Implicit, Never, Always };
 
+// For -z gcs-report= and -zgcs-report-dynamic
+struct GcsReportPolicy {
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MaskRay wrote:

We don't need a struct that wraps the enum. Just define an `enum` with a free function that converts the enum to "warning"/"error".

https://github.com/llvm/llvm-project/pull/127787