[compiler-rt] [compiler-rt][rtsan] Use Die instead of exit, define cf.exitcode (PR #107635)

[Florian Mayer via llvm-commits]

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@@ -35,6 +35,7 @@ void __rtsan::InitializeFlags() {
   {
     CommonFlags cf;
     cf.CopyFrom(*common_flags());
+    cf.exitcode = 43; // (TR-)808 % 255 = 43
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fmayer wrote:

please remove the comment, that just confuses people. add something like `// arbitrarily chosen`?

https://github.com/llvm/llvm-project/pull/107635