[compiler-rt] [sanitizer-common] [Darwin] Provide warnings for common sandbox issues (PR #165907)

[Dan Blackwell via llvm-commits]

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@@ -505,6 +505,13 @@ static void ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> *list,
   }
 
 #  if SANITIZER_APPLE
+  if (list.size() == 0) {
+    Report(
+        "WARN: No external symbolizers found. Symbols will be missing or "
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DanBlackwell wrote:

"will be missing" seems too strong here, could this be "may be missing"?

https://github.com/llvm/llvm-project/pull/165907