[clang] [analyzer] Fix [[clang::suppress]] for tricky template specializations (PR #178441)

[Ziqing Luo via cfe-commits]

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@@ -0,0 +1,33 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=core,debug.ExprInspection -verify %s
+// expected-no-diagnostics
+
+void clang_analyzer_warnIfReached();
+
+// Forward declaration
+namespace N { // 1st
+template <class T> struct Wrapper;
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ziqingluo-90 wrote:

hmm... actually, for `DeclWithIssue initially was 0xacad0d4d0  CXXMethod`,  there are two possibilities:
- it is the `CXXMethod` in the template definition; or
- it is the `CXXMethod` in the template specialization declaration.

Although none of their lexical parents should be in the second namespace,  I wonder if we try to start with a different `CXXMethod`, the result might be different🧐.

https://github.com/llvm/llvm-project/pull/178441