[compiler-rt] [rtsan] Only print out unique stack traces (PR #110028)

[Chris Apple via llvm-commits]

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@@ -49,7 +50,21 @@ static auto OnViolationAction(DiagnosticsInfo info) {
   return [info]() {
     IncrementTotalErrorCount();
 
-    PrintDiagnostics(info);
+    BufferedStackTrace stack;
+    stack.Unwind(info.pc, info.bp, nullptr,
+                 /*request_fast*/ true);
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cjappl wrote:

Took a look around and it seems like this is pretty common, despite whether or not the issue is fatal, the flag is used "on error".

I have moved to this approach, checking fast_unwind_on_fatal here.

Perhaps this flag should be renamed, but obviously that is a bigger discussion than this PR, and above my pay grade. Left a comment in the code describing what is going on

https://github.com/llvm/llvm-project/pull/110028