[compiler-rt] [sanitizer_common] fix shadowed ret hiding symbolizer read failures. (PR #209971)

[Paul Kirth via llvm-commits]

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@@ -68,4 +68,31 @@ TEST(Symbolizer, DemangleSwiftAndCXX) {
 }
 #endif
 
+#if SANITIZER_POSIX
+// Must live directly in __sanitizer (not an anonymous namespace) to match the
+// `friend class TestSymbolizerProcess` declaration in SymbolizerProcess.
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ilovepi wrote:

ctx_profile CtxInstrProfiling.h has a test that does manage to be in the anonymous namespace... though looking more closely it seems to be the test itself. Is it possible to just forward declare the class in the anonymous namespace and then this class won't need any special handling? I don't think that's a blocker either way, but if we don't need the extra coordination, then all the better.

https://github.com/llvm/llvm-project/pull/209971