[lld] [LLD][COFF] Add -build-id flag to generate .buildid section. (PR #71433)

[via llvm-commits]

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@@ -299,6 +299,8 @@ def : Flag<["--"], "time-trace">, Alias<time_trace_eq>,
 def time_trace_granularity_eq: Joined<["--"], "time-trace-granularity=">,
     HelpText<"Minimum time granularity (in microseconds) traced by time profiler">;
 
+defm build_id: B<"build-id", "Generate build ID", "Do not Generate build ID">;
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zmodem wrote:

Should we mention, here or in a doc somewhere, that this is always on when generating a PDB?

https://github.com/llvm/llvm-project/pull/71433